Dendrology terminology glossary - Recently Updated Pages

Cells and Tissues of Plants

leewilliams — Tue, 18 Dec 2007 03:54:26 CST

Albuminous cell
Annular cell walls
Apical meristems
Boarded pit pairs
Bordered pit
cell wall
Cellulose
Chlorenchyma
chloroplast
Collenchyma
Companion cell
Compound leaf
Cork cambium
Cork cells
Cortex
cytoplasm
Dermal tissue system
endoplasmic reticulum- Lee Williams
Epidermis
Fiber - Sarah Slater
Golgi complex
Ground tissue system
Guard cells
Heartwood
Lateral meristems
Lignin
Lumen-Lumen
Meristematic tissue
mitochondria - Tyler Parnall
Parenchyma - Kevin Christie
Pectin
Perforation plate
Periderm
Phloem
Pith
plasma membrane - Andrea Chapman
plasmodesmata - Morgan Traverse
plastids - Tori Waites
Primary meristems
protoplast
ribosomes
Root hair
Sclereid
Sclerenchyma
Sieve cell
Sieve elements-Lee Williams
Sieve plate
Sieve tube element
Simple pit
Suberin
Subsidiary cell
tonoplast- Conyr Aird
Trachery elements
Trichome
vacuoles - Sarah Slater
Vascular tissue- Conyr Aird
Vascular tissue system
Xylem

DEFINITIONS
Please insert your definitions in alphabetical order
Albuminous cell: A specialized parenchyma cell in a gymnosperm. They are thought to perform the same functions as companion cells, for the sieve cellsthey are associated with. This cell has a nucleus as well as other cytoplasmic parts generally found in living cells. Since they are so closely associated with sieve cells, they die when the sieve cells they are linked to die. (Biology of Plants, 7th edition, Peter H. Raven, 522) (Garden Web) http://glossary.gardenweb.com/glossary/albuminous_cell.html) By Caitlin Deas

Annular cell walls
Annular cell walls are a growth layer formed during a single year, in the secondary xylem or secondary phloem (Biology of Plants 6th Edition). Of or pertaining to a ring or rings; ring-like, ring-formed, ringed. annular space: the space between an inner and an outer ring. (Oxford English Dictionary)-Derek Burdikin

Apical meristems(Daniel Struthers): Are found at the tips of all shoots and roots and are composed of cells that are capable of repeated division. Apical meristems are involved with extension of the plant body(Primary growth).The apical meristems of both shoot and root are of great importance, because these tissues are the source of virtually all the new cells responsible for the development of the seedling and the adult plant.( Biology of Plants, 7th edition, Peter H. Raven, pg. 498). There are three types of apical meristems, including root, shoot, and stem apical meristems. The root apical meristem (RAM) is covered by the root cap which protects the apical meristem from the rocks, dirt and pathogens. Stem apical meristem is multicellular and, unlike the root apical meristem, has no cover. Rudimentary leaves may develop as scales, hardening at the end of the growing season to protect the stem apical meristem.(wikipedia online).

Bordered Pit – A pit in which the secondary wall arches over the pit membrane (Biology of Plants, 7th edition, Peter H. Raven,
Glossary pg G-3). Picture from www.uri.edu/cels/bio/plant_anatomy/images/9A.gif (Jackie Taylor)

Enhancement: "Bordered pits are structures found in the conductive tissues of many plants that allow for fluids to pass from one cell to another. The tracheids, which transport liquids, are dead cells; their contents decomposed, they are essentially empty. Simple pits are areas of the tracheid cell wall so thin that nutrient rich solutions can pass through them, to be dispersed throughout the plant. Bordered pits have the secondary cell wall extending over the pit with a small hole in the secondary cell wall that allows the water to pass through. When looking at a bordered pit under the microscope, it has the appearance of a donut. The hole of the donut is the pore and the outer ring of the donut is the margin of the bordered pit." (http://www.microscopyu.com/galleries/dxm1200/borderedpitssmall.html) (Biology of Plants, Peter H. Raven, pg.56) Krista N
Cell Wall The cell wall is a firm membrane that borders that of plant, some protits and some prokaryotic cells (Raven, G-4) . It is not found in animal cells. The cell wall serves as a protective layer and helps keep the cell rigid. It is often composed of cellulose and also helps to prevent infection. http://dictionary.reference.com/browse/cell%20wall
http://www.sigmaaldrich.com/img/assets/22940/Plant-Cell-Wall.jpg
Enhancement:
The cell wall helps keep the structure of the cell, by not breaking. The amount of pressure applied to the cell wall from the vacuole being filled with water is referred to as the turgor pressure. http://library.thinkquest.org/C004535/media/cell_wall.gif _Nick N
Enhancement: “Think of the cell wall as a wicker basket in which a balloon has been inflated so that it exerts pressure from the inside. Such a basket is very rigid and resistant to mechanical damage. Thus does the plant cell gain strength from a flexible plasma membrane pressing against a rigid cell wall.” (Howland, John L. (2000). The Surprising Archaea: Discovering Another Domain of Life. Oxford: Oxford University Press, 69-71.) (Russ Fountain)

Cellulose: A structural polysaccharide of cell walls consisting of glucose monomers joined by B-1, 4-glycosidic linkages (Biology 7th edition, Campbell Reece, pg. 72). A carbohydrate; the chief component of the cell wall in plants and some protists; an insoluble complex carbohydrate formed of microfibrils of glucose molecules attached end to end (Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-4). Matti
Cellulose occurs naturally in such fibrous produstc as, cotton and kapok, and is the raw material of many manufactured goods such as, paper, rayon, and cellophane. It's molecular formula is C6, H12, O5. (Merriam-Webster Online) Lee Williams
A complex carbohydrate consisting of 3000, or more glucose units. Cellulose comprises about 33% of all vegetable matter, and is the most abundant of all naturally occuring natural organic compounds. Nondigestible by man, cellulose is a food for herbivorous animals, because they retain it long enough for digestion by micro-organisms. Other cellulose derivitaves are used as adhesives, explosives, thickening agents for foods, and in moisture proof coatings. (Encyclopedia Britannica Online) Lee Williams

Cellulose Magnified:

Science Source, Photo Researchers, Inc.
Lee Williams

Chloroplast: a complex, discrete green structure, or organelle, contained in the cytoplasm of plant cells. Chloroplasts are responsible for the green color in plants. Chloroplast is where the photosynthesis occurs. (The Columbia Encyclopaedia, Sixth Edition) Chloroplast is the structure within a green plant cell in which photosynthesis occurs. They come as three different shaped plastids; round, oval, or disk-shaped. (Encyclopaedia Britannica online) Travis Unsworth Addition - inside the chloroplast the material is called the stroma. Within this stroma are sacks of thylakoids which is the site where photosynthesis takes place. The actual process occurs in the membrane of the thylakoid where light strikes chlorophyll a in such a way as to excite electrons to a higher energy state. Through a series of protiens (electron transport process) the electrons are brought down in energy level releasing energy to form ATP and NADPH. Another form of this is photophosphorylation where two photosystems are linked by a proton pump. This creates a transmembrane proton gradient which is used to synthesize ATP. (http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPS.html) (Mike Tomlinson)

This is a photo of a typical chloroplast that can be found in a plant cell.This picture shows the inner and outer membranes, the inner membrane space, stroma lamellae, stroma, thylakoids, and granum.

Photo From: Molecular Expressions, http://micro.magnet.fsu.edu/cells/chloroplasts/images/chloroplastsfigure1.jpg
(Photo added by Jessica W)
Enhancement: There are approximately half a million chloroplasts per square millimeter of leaf surface. Chloroplasts are primarily located in the cells of the mesophyll – tissue in the interior of the leaf. Mesophyll cells usually contain 30 – 40 chloroplasts. (Biology, 6th Edition, Neil A. Campbell, pg 178) - Tori Waites

Chlorenchyma: Parenchyma cells which contain cholorplasts (Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-5). Picture from http://www2.mcdaniel.edu/Biology/botf99/tissimages/chlorenchyma.jpg (Jackie Taylor)

Addition: the chlorenchyma are the main photosynthetic cells of the plant and manufacture carbohydrates during photosynthesis. (www.botany.uwc.ac.za) Mark Haywood-Farmer
Enhancement: (Katherine Loewen) The palisade mesophyll in leaves, where photosynthesis takes place, consists of specialized chlorenchyma cells (bugs.bio.usyd.edu.au)
Enhancement Nicole L Plant tissue consisting of parenchyma cells that contain chloroplasts and forming the basic green tissue of plant leaves and stems.
(Dictionary.com http://dictionary.reference.com/browse/chlorenchyma)

Collenchyma: Collenchyma tissues are mainly found under the epidermis in young stems in the large veins of leaves. The cells are composed of living, elongated cells running parallel to the length of organs that it is found in. Collenchyma cells have thick cellulose cell walls which thickened at the corners. Intercellular air spaces ar absent or very small. The cells contain living protoplasm and they sometimes contain chloroplasts. The collenchyma serve as supporting and strengthening tissue and if chloroplasts are present in collenchyma, photosynthesis takes place. (www.botany.uwc.ac.za) A supporting tissue composed of collenchyma cells—elongated living cells with unevenly thickened, non-lignified primary cell wall. (Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-6) Mark Farmer

Enhancement by Caitlin Deas:
This is a picture of a transverse section of collenchyma tissue. The dark pink areas in the center of the picture are the unevenly thickened cell walls. (University of Hawaii at Manoa Botany) http://www.botany.hawaii.edu/faculty/webb/BOT410/anatweb/images/ParColSclr/CollenColeusTolBl400.jpg

Companion Cell: Relatively small plant cell, with little or no vacuole, found adjacent to a phloem sieve tube and originating with the latter from a common mother cell. Thought to be involved in translocation of sugars in and out of the sieve tube.(www.mblab.gla.ac.uk) A specialized parenchyma cell associated with a sieve-tube element in angiosperm phloem and arising from the same mother cell as the sieve-tube element.( Biology of Plants, 7th edition, Peter H. Raven, glossary pg. G-6) Mark Haywood-Farmer

Enhancement: The sieve tube elements lack nucleoli, and therefore are dependent of the companion cells to provide important molecules such are proteins and the energy required for maintenance. The cells are connected through cytoplasmic threads called plasdomata. Kirsten.
Enhancement: (Dennis Murengi)-Below is an image of companion cells adjacent to the sieve tube. (www.visit-islay.com) http://www.visit-islay.com/resources/plants_files/image016.gif

Compound leaf:
A compound leaf is a leaf that is divided into several smaller leaves called leaflets, each of which has its own petiole (called a petioule). There are two types of compound leaves, pinnately compound and palmately compound. In palmately compound leaves, the leaflets are attached to the end of the leaf’s petiole. In pinnately compound leaves, the leaflets are attached to either side of the length of the leaf’s petiole. Compound leaves allow a plant to maximize the amout of sunlight a absorbed for photosynthesis. (Everything2: http://everything2.com/index.pl?node_id=1547316) (Raven 7th ed.)
Katherine Loewen

Enhancement (Andrea Chapman) Picture of two types of pinnately compound and one type of palmately
compound leaf ( Glossary - http://www.scarborough.k12.me.us/high/projects/trees/compound.gif)

Cork Cambium: The lateral meristem that forms the periderm, producing cork (phellem) toward the surface (outside) of the plant and phelladerm toward the inside; common in stems and rots of gymnosperms and woody angiosperms. Also called phellogen. ( Biology of Plants, Raven Evert Eichhorn, 525-526 ) .A cylinder of meristematic tissue in woody plants that replaces the epidermis with thicker, tougher cork cells.( Biology, seventh edition, Campbell Reece, 720) Dusite
Enhancement (Derek Burdikin)

http://www.kidsgardening.com/onlinecourse/Diagrams/c3/c3-12bark.gif
Enhancement: Cork cumbium produces secondary tissues from a ring of vascular cambium in stems and roots. Secondary phloem forms along the outer edge of the cambium ring, and secondary xylem (i.e., wood) forms along the inner edge of the cambium ring (Britannica online). Tamiki N

Cork cells: A secondary tissue produced by a cork cambium ; made up of polygonal cell, nonliving at maturity, with suberized cell walls, which are resistant to the passage of gases and water vapor ; the outer part of the peirderm. Also called phellem ( Biology of Plants, Raven Evert Eichhorn, Pg 525 ). A layer of usu. Suberized cells produced outwardly by a phellogen. ( Merriam-Webster's
Collegiate dictionary- Seventh ed.) Dustie

the outer darker part is the cork cambium. Dustie
Enhancement(Sarah Slater): Cork cells are non living, as mentioned above and therefore creates a protecting and insulating layer around the living cells in a stem or trunk. The thickness of the cork cell layers varies from species to species. The cork cells from the cork oak tree are what we commonly know as corks used in bottling wine. The cork oak tree grows in harsh Mediterranean conditions, and therefore produces more cork cells for protection, that is why it is the source of most cork used around the world.
Florida State University and Nikon
<http://www.microscopyu.com/galleries/confocal/corkcells.html>
How Stuff Works (founded by Carolina State University Prof)
<http://science.howstuffworks.com/question550.htm>

Enhancement: Cork is composed of dead cells that accumulate on the outer surface of the cork oak tree. Because of its honeycomb-like structure, cork consists largely of empty space; its density (weight per unit volume) is one-fourth that of water. Unlike a honeycomb, however, cork consists of irregularly shaped and spaced cells having an average of 14 sides. With 625 million of these empty cells per cubic inch (40 million per cubic centimeter), cork is like many layers of microscopic Bubble Wrap, making it an effective cushioning material. Its low density makes cork useful in products like life preservers and buoys. The large amount of dead-air space makes cork an effective insulation material for both temperature and noise. (http://www.madehow.com/Volume-5/Cork.html). (Russ Fountain)

Cortex – Ground-tissue region of a stem or root bounded externally by the epidermis or internally by the vascular system; a primary-tissue region; also used to refer to the peripheral region of a cell protoplast. Biology of Plants 7th ed. Peter H. Raven, Pg. G-6)A complex layer of tissue between the epidermis or the corky layer and the vascular tissue of a stem or root, made up mainly of parenchyma cells. (Gage Canadian Dictionary, Pg. 266). Jessica W.
Enhancement: Cortical cells may contain stored food or other substances, such as resins, latex, essential oils, and tannins. Cortical cells in herbaceous stems, young woody stems, and stems of succulents contain chloroplasts and can therefore make food by photosynthesis. (Encyclopedia Britannica Online) - Nicole H.

Picture from: Botany Basics; http://extension.oregonstate.edu/mg/botany/images/fig3-big.gif
Cytoplasm: The cytoplasm is the living matter of the cell not including the nucleus; it can also be called the protoplasm (Raven G-7). It is full of proteins that control cell functions and contains the vital organelles. It is a jelly like material found in eukaryotic cells. http://dictionary.reference.com/browse/cytoplasm --John
Enhancement: (Dennis Murengi)-Cytoplasm functions as a "molecular soup" that holds together all of the cell's organelles, and divides the organelles within the cell. Cytoplasm is thought to be the "home"of the cytoskeleton; the cytoskeleton provides movement of the cell as well as its shape through the "cytoplasmic streaming", when the cytoskeleton moves to push the cell membrane it is then when the cytoplasm moves and fills the empty space. Proteins that occur in the cytoskeleton help to keep the shape of the cell, for the proteins are known to be used for "intracellular support". Within the cytoplasm there are also "microtubules" which function as cell dividers, they are known for "temporary scaffolding"-for the other organelles. Actin Filaments are also found in cytoplasm and they also contribute to cell division as well as cell motility. (www.sun.menloschool.org)
http://sun.menloschool.org/~birchler/cells/plants/cytoplasm/structureandfunction.html

Dermal Tissue System (Brian France): Makes up the outer protective covering of the plant.(Biology of Plants, Raven) Consisting of the epidermis(Paraenchyma cells) and periderm(Cork cells). The major role of the epidermis is to regulate the size of the stomata, which regulates water loss and the exchange of oxygen and carbon dioxide. The primary function of the Periderm is support and protection.(Plants, Their Biology and Importance.Kaufman)

Enhancement(LaceyL):

http://www-plb.ucdavis.edu/labs/rost/Rice/Stems/xsstem1.gifOccurs in all organs of the plant, and is continuous from organ to organ and reveal the basic unity of the plant body (Biology of Plants, Raven, pg 369).

Enhancement: Dermal Tissue system is the outer protective layer of the primary plant body (the roots, stems, leaves, flowers, fruits, and seeds). The epidermis is usually one cell layer thick, and its cells lack chloroplasts (Britannica online). Tamiki N

Endoplasmic Reticulum: A system of interconnected vesicular and lamellar cytoplasmic membranes that functions especially in the transport of materials within the cell and that is studded with ribosomes in some places. (Merriam-Webster Online, http://www.m-w.com/dictionary/endoplasmic%20reticulum ). It's a continuous membrane system that forms a series of flattened sacs within the cytoplasm of a eukaryotic cell and is important in the biosynthesis, processing, and transport of proteins and lipids. The ER usually constitutes more than half of the membranous content of the cell and is continuous with the outer membrane of the nuclear envelope. (Encyclopedia Britannica Online, http://www.britannica.com/eb/article-9032619/endoplasmic-reticulum). Lee Williams

Epidermis: The epidermis is the outermost layer of leaf cells and young roots and stems which plays a key role in protection (Raven, pg. 5). It is composed of a single layer of living cells that are very tightly packed without intracellular space. This layer of cells covers all surfaces of a plant and its outside, waxy layer, the cuticle, plays a role in preventing evaporation of water. Since plants undergo photosynthesis, gas exchange occurs at the epidermis through small openings, stomata, which are generally found on the underside to leaves. As well, epidermal cells are clear so sunlight can pass through its layer into chloroplasts (“leaves”, <scidiv.bcc.ctc.edu>).~Quinn

Enhancement (Kristie Seaborn) Epidermal cells usually do not exactly fit together, but there are small voids between the individual cells. These voids between individual epidermal cells are filled up by cuticle plugs which are termed anticlinal walls.

(http://www.uni-muenster.de/GeoPalaeontologie/Palaeo/Palbot/cuticles.htm)

Fiber (Sarah Slater): Fiber cells are a part of the ground tissue system, more specifically a type of sclerenchyma cell that is found in plants. Sclerenchyma cells have very thick secondary walls, and useful for adding strength and support to the plant. Therefore fiber cells add strength to a plant. They are very slim, lengthy, and found in bundles. Fiber extracted from the leaves is called leaf fiber and used to make useful products such as hemp, twine and rope, and are often woven together to create fabric. Fiber extracted from the stem of a plant is called bast fiber, and is stronger than leaf fiber. It is used in the making of heavy-duty fabrics.

Encyclopaedia Britannica Online <http://www.britannica.com/eb/article-9047504/leaf-fibre>
Biology of Plants. Raven. Pg 515

The fiber cell can be seen in the diagram below.

Portion of a picture from: University of California <http://www.ucmp.berkeley.edu/IB181/VPL/Ana/Ana1.html>

Enhancement: Fiber cells are dead at matuarity. They are associated with the xylem and phloem tissue of monocot and dicot stems and roots, but generally not found in gymnosperms. In fact, the primary reason why gymnosperm woods are generally softer and lighter than angiosperm woods is the presence in angiosperm wood of dense clusters of heavily-lignified, thick-walled fiber cells. The densely-packed fiber cells greatly increase the hardness and density of angiosperm woods (http://waynesword.palomar.edu/traug99.htm) Tamiki N

Guard Cells (R.Swite)
In plants, a specialized cell on the undersurface of leaves for controlling gas exchange and water loss. Guard cells occur in pairs and are shaped so that a pore, or stomata, exists between them. They can change shape with the result that the pore disappears. During warm weather, when a plant is in danger of losing excessive water, the guard cells close, cutting down evaporation. http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0035144.html Guard cells are located in the leaf epidermis and pairwise surround stomatal pores, which allow CO2 influx for photosynthetic carbon fixation and water loss via transpiration to the atmosphere. Signal transduction mechanisms in guard cells integrate a multitude of different stimuli to modulate stomatal aperture. Stomata open in response to light. In response to drought stress, plants synthesize the hormone abscisic acid (ABA) which triggers closing of stomatal pores. Guard cells have become a well-developed system for dissecting early signal transduction mechanisms in plants and for elucidating how individual signaling mechanisms can interact within a network in a single cell. http://www-biology.ucsd.edu/labs/schroeder/clickablegc.html

figure 1 Gaurd cell (RSwite) www.fhsu.edu/biology/thomasson/dicot2.JPG

Enhancement: Guard cells contain nearly always chloroplasts, and subsidiary cells that are usually devoid of chloroplasts http://www.biologie.uni-hamburg.de/b-online/e32/32f.htm Tamiki N

Golgi Body – In eukaryotes, a group of flat, disk-shaped sacs that are often branched into tubules at their margins; serve as collecting and packaging centers for the cell and concerned with secretory activities; also called dictyosomes. The term Golgi apparatus (also called Golgi complex) is used to refer collectively to all of the Golgi bodies, or dictyosomes, of a given cell. (Biology of Plants 7th ed. Peter H. Raven, Pg. G-10) An organelle, consisting of layers of flattened sacs, that takes up and processes secretory and synthetic products from the endoplasmic reticulum and then either releases the finished products into various parts of the cell cytoplasm or secretes them to the outside of the cell. (Dictionary.com Unabridged V 1.1)
(http://dictionary.reference.com/browse/golgi%20apparatus) Jessica W.

Picture from: Molecular expressions; http://micro.magnet.fsu.edu/cells/golgi/images/golgifigure1.jpg

Ground System:Plant tissue system, composed mainly of parenchyma cells with some collenchyma and sclerenchyma cells, that occupies the space between the epidermis and the vascular system; is involved in photosynthesis, water and food storage, and support; one of the four main tissue systems in plants.(http://www.emc.maricopa.edu/faclty/farabee/biobk/BioBookglossG.html#ground%20system) All tissues other than the epidermis (or periderm) and the vascular tissues; also called fundamental tissue.( Raven EE, glossary) Amanda Last
Enhancement: Liz Foster
The ground tissue system makes up most of the mass of the tree. It is derived from apical meristem.

A picture showing the ground tissue system.

Heartwood (Russ Fountain)
Dead, central wood of trees. Its cells usually contain tannins or other substances that make it dark and sometimes fragrant. Heartwood is mechanically strong, resistant to decay, and less easily penetrated by wood-preservative chemicals than other types of wood. One or more layers of living and functional sapwood cells are periodically converted to heartwood.(Britannica Concise Encyclopedia.- http://www.answers.com/topic/heartwood).

Notice that most of the secondary xylem is a darkish color. This is heartwood (purple line above). Only a small portion of the secondary xylem - the portion just inside the vascular cambium - is white. That is sapwood (green line). (“The Origin of Growth Rings” – Cornell University. http://instruct1.cit.cornell.edu/courses/biog105/pages/demos/105/unit5/growthrings.html) - Russ Fountain

Enhancement Heartwood is the central wood core no longer serving for the conduction of water or dissolved minerals. Heartwood is usually denser than sapwood. ( Columbia Encyclopaedia Six Edition) Jessi.E.W.

Lateral Meristem(LaceyL): Is a meristem that give rise to secondary tissue. Meristems are embryonic tissue regions capable of adding cells indefinitely to the plant body (Biology of Plants, Raven, pg. 6). The lateral meristem is the meristem that thickens the roots and shoots of woody plants. The vascular cambium and cork cambium are lateral meristems (Biology, 7th Edition, Campbell and Reece, pg. 720). Enhancement and picture by Mike Tomlinson

The vascular and cork cambium are a cylinder of dividing cells that runs most of the length of stems and roots. The two types of lateral meristems each produce different parts of the tree, the cork cambium preduces the secondary xylem to the inside and secondary phloem to the outside. The cork cambium is part of the periderm and creates the outer bark of the tree, producing waterproofing and protective cork tissue at the surface of the stem and root. http://www.phschool.com/science/biology_place/biocoach/plants/lateral.html
Mike Tomlinson Enhancement

Lignin: One of the most important constituents of the secondary wall of vascular plants, although not all secondary walls contain lignin; after cellulose, lignin is the most abundant plant polymer. (Biology of Plants, 7th edition, Peter H. Raven, glossary pg. G-13) Refers to a group of phenolic polymers that confer strength and rigidity to the woody cell wall of plants. These compounds make up the second most abundant class of chemicals found in wood. (www.lignin.org/01augdialogue) Mark Haywood-Farmer
Enhancement: Lignin: integral part of the cell walls of plants it fills the spaces between cellulose, hemicellulose and pectin components, especially in tracheids, sclerids, and xylem it also plays a crucial part in conducting water in plant stems. Fig. Lignin, Cellulose and hemicellulose are the three main components. Ref: Davin, L.B.; Lewis, N.G. (2005). "Lignin primary structures and dirigent sites". Current Opinion in Biotechnology 16: 407-415. Lignin and its Properties: Glossary of Lignin Nomenclature. Dialogue/Newsletters Volume 9, Number 1. Lignin Institute (July 2001). Scott Horley

Lumen (Derek Burdikin)
Lumen is an inner space, tubular passage or cavity in an organism or cell (Biology of Plants 6th Edition). Lumen isLatin for an opening for light; the space bounded by the plant cell wall; the thylakoid space in chloroplasts (Oxford English Dictionary 5th Edition.)
Enhancement (Katherine Loewen): These structures occur in various cell organelles including the nuclear envelope, the golgi body and the endoplasmic reticulum (Raven, 6th ed.)

Ehancement(Brian France) http://student.biology.arizona.edu

Meristematic Tissue: Meristematic tissue – which is derived from the word “merismos” meaning “division” – is embryonic tissue that is responsible for the growth of trees through the formation of new cells by division. This tissue consists of apical meristems, which are responsible for the extension of roots and stems (primary growth), and lateral meristems, which are responsible for the thickening of roots and shoots (secondary growth). Meristematic tissue gives rise to roots, stems, leaves and flowers. Its continued presence in the tips of roots and stems after embryogenesis allows for indeterminate growth (Biology of Plants, 7th Edition, Peter H. Raven, pg 6 and 510). Some of the meristematic cells (initial cells) remain in the meristem to maintain it, while others (derivative cells) are incorporated into other tissues where they divide repeatedly and specialize (Biology, 6th Edition, Neil A. Campbell, pg 729). - Tori Waites
Enhancement: (Jessica Wrench) This is a diagram of a root tip which displays different meristematictissues. Photo from: http://www-plb.ucdavis.edu/labs/rost/Tomato/Roots/closed.gif

Parenchyma (Katherine Loewen)
Parenchyma is the most common of the three types of ground tissue. Parenchyma cells are isodiametric (spherical in shape but with flat faces), living at maturity, and usually have only primary cell walls. (Salisbury 4th ed.) They occur throughout the plant in the pith, cortex, and mesophyll. Parenchyma cells perform numerous and essential functions such as photosynthesis, secrection, and storage. An especially important feature of parenchyma cells is that they retain their meristematic ability at maturity and therefore play and important role in wound healing and regeneration. (Raven 6th ed.) -Enhancement (Kevin Christie) - Living, generally thin-walled cell of variable size and form; the most abundant kind of cell in plants.(Raven 513)
1857 Littell's Living Age 11 Apr. 126/2 The sap in the wood cells moves upward through them, that in the *parenchyma cells through them. 1899 T. C. ALLBUTT Syst. Med. VI. 249 Emboli of air, of fat and of parenchyma-cells. 1927 Bot. Gaz. 84 355 The lacunae..continue to stain for some time after their occlusion by parenchyma cells has begun. 1982 K. ARMS & P. S. CAMP Biol. (ed. 2) iv. 62 Parenchyma cells from various tissues that make up most of the inside of leaves and of non-woody stems and roots. (Oxford English Dictionary Online)
Enhancement-(Danielle Dornik)

large vacuoles and distinct intercellular spaces.
the most important function is for the storage of food and water
intercellular air spaces permit gaseous exchange(http://www.botany.uwc.ac.za/SCI_ED/grade10/plant_tissues/parenchyma.htm) (http://www.bio.txstate.edu/~dlemke/botany/1410lab/lab_exercises/lab3/tissues/parenchyma.html)

Pectin:
A highly hydrophilic polysaccharide present in the intercellular layer and primary wall of plant cell walls; the basis of all fruit jellies. (Biology of Plants 6th Edition) - Brian France
Enhancement: Pectin is the matrix in which the cellulose framework of the plant wall is embedded within. Pectin imparts plastic or pliable properties to the cell wall due to their highly hydrophilic nature, a condition necessary for wall expansion.
Amanda M Enhancement: Pectin is found in fruit and vegetables. Pectin can be used as a thickener, water binder and stabilizer, and as a gelling agent. – Tyler Parnall http://www.lsbu.ac.uk/water/hypec.html
Enhancement: Pectins are characteristic of the first-formed (primary) cell wall layers and the the intercellular substance (middle lamella) that cements together the walls of contiguous cells. They are highly hydrophilic polysaccharides, and the water they attract to the cell imparts plastic, or pliable, properties to the wall, a condition necessary for wall expansion. ( Biology of Plants 6th Edition, pg. 53) Robin Anders

Perforation plate: (Katherine Loewen)
Perforation plates occur on the ends of vessel elements and serve to allow the rapid flow of water from cell to cell. They can allow this rapid movement of water because they have holes in their secondary and primary cell walls called perforations. (Raven 6th ed.)These structures also keep bubbles that form in the water being transported from coalescing and obstructing flow. (Salisbury 4th ed.)

Enhancement(LaceyL):

Sieve Elements: In flowering plants the conducting elements in the phloem are called sieve elements and consist of sieve cells and sieve-tube members, the latter differing in having some sieve areas specialized into sieve plates (generally on the end walls). (Encyclopedia Britannica Online, http://www.britannica.com/eb/topic-543478/sieve-element ) The principal cells of phloem, the sieve elements, are so called because of the clusters of pores in their walls through which the protoplasts of adjoining cells are connected. Two types of sieve elements occur: sieve cells, with narrow pores in rather uniform clusters on the cell walls, and sieve-tube members, with larger pores on some walls of the cell than on others. Although the sieve elements contain cytoplasm at maturity, the nucleus and other organelles are lacking. Associated with the sieve elements are companion cells that do contain nuclei and that are responsible for manufacturing and secreting substances into the sieve elements and removing waste products from them. (MSN Encarta Encyclopedia, http://encarta.msn.com/encyclopedia_761568511_4/Plant.html#p23 )

Epidermis/ Periderm: The epidermis is a thin surface layer of tissue in higher plants formed by growth of a primary meristem. (Merriam-Webster Online, http://www.m-w.com/dictionary/epidermis ). The epidermis and its waxy cuticle provide a protective barrier against mechanical injury, water loss, and infection. Various modified epidermal cells regulate transpiration, increase water absorption, and secrete substances. (Encyclopedia Britannica Online, http://www.britannica.com/eb/topic-543478/sieve-element )
The Periderm isthe outer layer of plant tissue in woody roots and stems (MSN Encarta Encyclopedia, http://encarta.msn.com/dictionary_1861725029/periderm.html ), consisting of the cork cambium and the tissues produced by it, such as cork ( The Free Online Dictionary, http://www.thefreedictionary.com/periderm).
The key difference between epidermis and the periderm is that epidermal tissue is young tissue produced by primary meristem, while the periderm consists of woody cork produced by the lateral meristems. (Lee Williams)

Sieve cell/Albuminous cell
Both the Sieve cells and the Albuminous cells are food conducting cells in the phloem in gymnosperms. They both have primary cell walls, they are generally elongated in shape
Sieve cells are associated with albuminous cells, which lack starch, thus making it possible to differentiate them from phloem parenchyma. Albuminous cells have many plasmodesmatal conections with sieve cells, as they are believed to play a role in the delivery of substances to the sieve cell. Since albuminous cells are so closely associated with sieve cells, they die when the sieve cells they are linked to die.
Generally not derived from the same mother cell. (Biology of Plants 6th Edition)-Derek Burdikin
Perforation plates/ sieve plates

Sieve plate: The part of the wall of sieve-tube elements bearing one or more highly differentiated sieve areas. ( Biology of Plants, Raven Evert Eichhorn Pg 520). An end wall in a sieve-tube member, which facilitates the flow of phloem sap in angiosperm sieve tubes. (Biology, seventh edition, Campbell Reece, 719)
Perforation plates: The part of the wall of a vessel element that is perforated. ( Biology of Plants, Raven Evert Eichhorn Pg 516). End walls of vessel elements that enable water to flow freely through the vessel. (Biology, seventh edition, Campbell Reece, 719) These two definitions are similar, showing that both plates facilitate the flow of xylem or phloem in the cells of trees. The difference is perforation plates are found in water conducting cells of the xylem and sieve plates are found in the sugar-conducting cells of the phloem.
Dustie

Protoplast/Tonoplast: Most of the metabolic activities of the cell—the chemical reactions of living systems—occur within protoplasts(Encyclopedia Britannica Online, http://www.britannica.com/eb/article-73102/angiosperm ). The cell wall are the living contents of the cell, called the protoplast. These contents are bounded by a cell membrane composed of a phospholipid bi-layer. The protoplast contains the cytoplasm, which in turn contains various membrane-bound organelles and vacuoles and the nucleus, which is the hereditary unit of the cell. (MSN Encarta Encyclopedia, http://encarta.msn.com/encyclopedia_761568511_2/Plant.html#p12 ).
A tonoplast is the separating membrane in a plant cell: the semipermeable membrane separating a fluid-filled internal cavity vacuole from the surrounding cytoplasm inside a plant cell (MSN Encarta Encyclopedia, http://encarta.msn.com/dictionary_1861720832/tonoplast.html ). The protoplast functions to contain organelles within the cytoplasm, and the tonoplast contains the vacuole, separating it from the cytoplasm. Lee Williams

Lenticels/Guard cells Lenticels: Small raised areas in the bark of stems and roots that enable gas exchange between living cells and the outside air. (Biology, seventh edition, Campbell Reece, 728) Spongy area in the cork surface of stems, roots, and other plant parts that allow interchange of gases between internal tissues and the atmosphere through the periderm; occur in vascular plants. (Biology of Plants, Raven Evert Eichhorn Pg 586-587) Guard cells: The two cells that flank the stomata pore regulate the opening and closing of the pores (Biology, seventh edition, Campbell Reece, 724). Pairs of specialized epidermal cells surrounding a pore, or stoma; changes in the turgor of a pair of guard cells cause the opening and closing of the pore. (Biology of Plants, Raven Evert Eichhorn Pg 523, 524f) The similarities between lenticels and guard cells is each play the roll in gases exchange and both are hole of gases exchange. The difference is that the lenticels are on the outside of the tree and are like little cuts that allow the exchange to take place between the atmosphere and tree. Guard cells are cells that regulate the flow of gas exchange inside the bark. Dustie
Golgi Body and The Endoplasmic reticulum
The golgi body and the endoplasmic reticulum are very closely related, not in function but in the process of metabolism within the cell. The golgi body's primary function is to process and package macromolecules which are produced by the cell, specifically by the RER and the SER. The golgi specializes in labeling macromolecules with protiens which confirm the macromolecules destination wiether it be exocytosis or for use within the cell. The golgi is directly related to the Endoplasmic reticulum through vessicular transport. This process is what transports macromolecules to the plasma membrane to be released from the cell and transports newly synthesized materials from the ER to the golgi. In the ER, transmembrane receptor protiens bind to the cargo molecules. The adaptin binds to the transmembrane protiens which in turn binds to the vesicle coat which causes the initial curvature of the ER membrane which results in vessicular budding. The vesicle soon buds off the ER and travels through the cytoplasm to the golgi. Vesicle docking takes place when a surface markers called snares finds its complementary snare on the golgi body. V-snares are located on the vessicle and t-snares or target snares are located on the golgi. These to sets of snares wrap around eachother with the help of a rab protien. This process brings the vesicle close to the golgi untll it reaches a distance of 1.5nm. This is the distance when the vessicle will begin to fuse to the membrane of the golgi. After this fusion the vesicle coat releases along with the adaptin and the cargo molecules are released. Lodish; et al. (2004). Molecular Cell Biology, 5th edn, W.H. Freeman and Company. Mike Tomlinson

Enhancement:
Three vesicle coats are related to vesicular transport, clathrin, COPI and COPII. Clathrin coats are involved with golgi transport to the plasma membrane, COPI is for retrograde transport from the golgi backto the ER and COPII coats are used in the anterograde transport from the ER to the golgi. Reference: Pelham, H.R.B. and J.E. Rothman, The Debate about Transport in the Golgi - Two Sides of the Same Coin? Cell, 2000. 102: p. 713-719.
-Nikki Heim

Mitochondria/Chloroplast: (Tyler Parnall) Mitochondrion: An organelle found in plant and animal cells. It is the site of cellular respiration. (Biology of Plants, 7th Edition, Raven, pg 45) Chloroplast: An organelle found primarily in plant cells. The Chloroplast is the sight of photosynthesis. (Biology of Plants, 7th Edition, Raven, pg 41-42) Comparison: Both mitochondria and chloroplasts are concerned with the production of energy. Both these organelles also originated as small bacteria. Both also contain their own DNA. Mitochondria produce energy primarily by breaking down sugars in both plant and animal cells, and are the predominant cells in heterotrophs. While Chloroplasts absorb sunlight to produce sugar and energy, Chloroplasts are responsible for sustaining autotrophs.

Ribosome: The Large and small Subunits The ribosome consists of two units, the large and the small subunit. The two units fit together and work together to translate the mRNA into a polypeptide chain which is the initial product of protein synthesis. The subunits of prokaryotic cells are made up of one or two large rRNA molecules and many small protein molecules. The eukaryotic ribosome is similar but consists of two or three large rRNA molecule. Recent research has shown that no ribosomal proteins are located at the reaction site of protein synthesis. This means that the protein portion of ribosomes act more as a scaffold and molding device that may enhance the rRNA to synthesize protein rather than actually taking part in the process. The eukaryotic Ribosomes are 80s in size consisting of a 60s large subunit and a 40s small subunit. The S units of the subunits cannot simply be added because they represent measures of sedimentation rate rather than of mass. The sedimentation rate of each subunit is affected by its shape, as well as by its mass.The large Ribosomal unit is split into three smaller units that are bound by proteins and the small Ribosomal subunit is one unit made up of 1900 nucleotides and approximately 33 protiens. The small subunit before the initiation of protein synthesis is bound to the tRNA containing the amino acid. This tRNA binds to the complementary codon of the mRNA and then recruits the large subunit afterwards. The two subunits join at the start codon and protein synthesis begins. The Large subunit has three tRNA binding sites which are designated A,P and E. The A site binds to a tRNA which is bound to an amino acid, the P site binds to a peptidyl-tRNA which is a tRNA that is bound to the peptide which is being synthesized, and the E site binds to a free tRNA just before it exits the ribosome. After the Ribosome reaches the stop codon which is bound to the last amino acid the ribosomal units push the tRNA to the exit site and then separate and the polypeptide is synthesized. The Molecular Biology of the Cell, fourth eddition. Brusce Alberts, et al. Garland Science (2002) pg. 342, Cech T (2000). "Structural biology. The ribosome is a ribozyme". Science 289 (5481): 878-9 Mike Tomlinson

Symbiotic Associations; Mycorrhial Fungi and Mycorrhizae

leewilliams — Thu, 29 Nov 2007 18:42:48 CST

Arbuscular mycorrhizal (AM) fungus Tamiki N
arbuscule Jake L
ascomycete
ascospore
ascus
basidiomycete(Daniel Struthers)
basidiospore
basidium
bimodal nutrition
commensalism - Mark Dinicol
ectomycorrhiza=Lacey L
endomycorrhiza
external hyphae(Daniel Struthers)
Gadgil effect - Aaren Secord
Hartig net - Mark Dinicol
heterotrophic(Daniel Struthers)
host - Aaren Secord
hyphae - Mark Dinicol
hypogeous - Aaren Secord
intercellular growth
interface - Scott Horley
intracellular growth= R.Swite
lichen= Lacey L
mantle Jake L
mutualism=R.Swite
mycelium
mycophagy
mycorrhiza-Danielle Dornik
parasite - Scott Horley
pathogen=R.Swite
rhizosphere - Scott Horley
saprophyte Ryan T
symbiosis JAke L
truffle
vesicle=Lacey L
zygomycete

Definitions (in alphabetical order) Arbuscular Mycorrhizal (AM) Fungus: The arbuscular mycorrhizal symbiosis is a mutualistic association formed between plants and a wide variety of fungi. Arbuscular mycorrhizae (AM) are the most common type of mycorrhizae on the planet. Ninety percent of all plant families contain AM species, and most mycorrhizasts believe that the vast majority of all land plants (from hornworts to grasses) are AM.The symbiosis is formed by the majority of the vascular flowering plants and is found in ecosystems throughout the world. In general, the symbionts trade nutrients, and the arbuscular mycorrhizal (AM) fungus obtains carbon from the plant while providing the plant with an additional supply of phosphorus (as phosphate). Tamiki N
Source: http://www.noble.org/MedicagoHandbook/pdf/ArbuscularMycorrhiza.pdf, http://botit.botany.wisc.edu/courses/mpp/AM.html
Enhancement: Below is a picture of Colonization of a flax root by Arbuscular Mycorrhizal Fungi. The black areas within the root are locations of transfer of phosphorus from the fungus to flax called Arbuscules. In exchange, the fungus obtain food energy from the flax. The thin black strands joining the Arbuscules are also the fungus and these extend into soil increasing the root system of the flax plant. http://images.google.ca/imgres?imgurl=http://www.umanitoba.ca/afs/graphics/fiw_tenuta_fig2.jpg&imgrefurl=http://www.umanitoba.ca/afs/fiw/060105.html&h=345&w=463&sz=49&hl=en&start=2&um=1&tbnid=EON1k6tSEjPdEM:&tbnh=95&tbnw=128&prev=/images%3Fq%3DArbuscular%2BMycorrhizal%2Bfungi%26svnum%3D10%26um%3D1%26hl%3Den -Nick N

Arbuscule An arbuscule is hypha that penetrates a root cornical cell, forming a tree-like structure. ( Mycorrhizas: Anatomy and Biology, Peterson, L., et.al. pg. 163) The arbuscule does not enter the protoplast, it surrounds the protoplast, and causes infolding and increasing of the protoplasts area. This increases the transfer of nutrients between the cell that the fungi. The hypha also extends out of the cell into the soil, increasing the absorption of water and nutrients of the cell. (Raven, pg. 292-293) Arbuscules are endomycorrhizae, made up of around 200 species of zygomycota fungi, and inhabit root cells of around 80 percent of vascular plants. This type of mycorrhizal fungi is totally dependent on plants as host cells (obligate biotrophs).(Mycorrhizas: Anatomy and Biology, Peterson, L., et.al. pg. 163) Jake

Enhancement:

Note the distinct tree like shape

http://biology.kenyon.edu/fennessy/SrexMarx/arbgood.jpg
--John

Ascomycete (Caitlin Deas)
The ascomycetes are one of two major groups in the septate fungi (the other is the basidiomycetes). They are septate since their hyphae have cross-walls, or septae. They usually produce a fruiting body (a mushroom-like growth), which produces the spores sexually. The spores (called ascospores) are produced inside little sac-shaped enclosures called asci in a layer in this fruiting body. (Nature Navigator) http://internt.nhm.ac.uk/jobj/runjava.jobj?java=ctol.CTOLServer&method=printNamePage&accountref=987&NAMEID=27084
They also reproduce asexually by forming nonsexual spores (conidia) at the ends of their hyphae. Some examples of ascomycetes are yeasts, morels, truffles, Dutch elm disease and ergot. (The Free Dictionary by Farlex) http://www.thefreedictionary.com/ascomycete
There are 15,000 species in 1,950 genera of ascomycetes. The lichens form the largest group. (The Free Dictionary by Farlex)http://encyclopedia.farlex.com/ascomycete

This is a picture of orange-peel fungus, Aleuria aurantia,a non-lichenised ascomycete fungus.

(Fathom)
http://www.fathom.com/feature/122560/3051_lichen9_SM.jpg

Ascospore: Type of sexual spore produced within the ascus; found in ascomycetes. 4-8 spores are produced in the Ascomycetes and are capable of asexual reproduction Biology of plants 7th edition http://www.britannica.com -Travis Unsworth

Enhancement(Andrea Chapman) Ascospores through an Electron Micrograph (AFTOL Project - http://www.clarku.edu/faculty/dhibbett/TFTOL/images/ascospore.jpg)

Enhancment(Jackie Taylor) - They are haploid cells formed after meiosis. Ascospores are unique structures that distinguish the ascomycetes from all other fungi. They are recognizable by the fact that they have no attachment points, and are sometimes enclosed in gelatinous sheaths or within a sac. Produced by morels, truffles, cup fungi, ergot and many micro-fungi. Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. 271-272 EM Lab P&K - https://www.emlab.com/app/fungi/Fungi.po?event=fungi&species=4&type=secondary

Ascus (Caitlin Deas)
The ascus is a sac-shaped enclosure in the fruiting body of an ascomycete. It contains the sexual ascospores, which are formed by an enveloping membrane system. In this system, mitosis follows meiosis to form eight nuclei, which become eight ascospores eventually. Below is a picture of Taphrina, the asci of the peach leaf curl fungus atop a peach leaf.

(Tree of Life Web Project)
http://www.tolweb.org/Ascomycota

Although the ascus usually generates only eight ascospores, there are some that produce many more (even thousands). (Illinois Mycological Association) http://www.ilmyco.gen.chicago.il.us/Terms/ascus134.html

Enhancement: The ascus is a saclike structure produced by fungi of the class Ascomycetes (sac fungi) in which sexually produced spores (ascospores), usually four or eight in number, are formed. Asci may arise from the fungal mycelium (the filaments, or hyphae, constituting the organism) without a distinct fruiting structure, as in the leaf curl fungi; it may arise within a fruiting structure (ascocarp) that may be exposed, as in the molds and powdery mildew fungi; or it may be imbedded in a compact structure (stroma), as in the ergot and black knot fungi. In the case of yeasts, a single cell converts to an ascus. (Encyclopedia Britannica Online, http://www.britannica.com/eb/article-9000538/ascus ). Lee Williams.

Basidiospore:
Spores produced by fungi in the family Basidiomycota (Raven, 7th ed.). Basidiospores are produced by reproductive cells called basidia through meiosis and nuclear fisson. They are uninucleate and haploid. When basidiospores are discharged they germinate to form the primary mycelia of a new fungus. (Introductory Mycology. Alexopoulos, C.J. and Mims, C.W., 1979) (Raven, 7th ed.)
Katherine Loewen

The arrow points to an example of a basidiospore. www.botany.hawaii.edu (Matti Harper)

Basidiospore (Enhancement) - When basidiospores encounter a favorable substrate, they may germinate, typically by forming hyphae. These hyphae grow outward from the original spore, forming an expanding circle of mycelium. Some basidiospores germinate repetitively by forming small spores instead of hyphae. (Tree of Life: Basidiomycota). Atypical mushroom produces billions of basidiospores. (The American Heritage Science Dictionary).
- Mark Dinicol

Basidium:
Club-shaped reproductive cell of the fungal family basidiomycota. Each basidium produces 4 basidiospores through meiosis and nuclear fisson. The basidiospores are borne on stalk-like structures called stigmata. (Raven, 7th ed.) (Introductory Mycology. Alexopoulos, C.J. and Mims, C.W., 1979)
Katherine Loewen
Basidium (Enhancemen)t: A reproductive appendage that produces sexual spores on the gills of mushrooms. (Biology 7th Edition, Campbell and Reece, pg. 618) Lacey Loewen

Basidium (Enhancement) - a microscopic, spore-producing structure found on the hymenophore of fruiting bodies of basidiomycete fungi. The basidium is unique to basidiomycetes and distinguishes them from other kinds of fungi. (The American Heritage® Science Dictionary)
Most basidiomycetes have single celled basidia, but in some groups basidia can be multicellular. (Ingold, 1998. Ballistosporic basidia).

Scanning electron micrograph of basidia on the gills of a toadstool. Note that each basidium produces four stalks (sterigmata) and the basidiospores develop on the ends of these stalks. (The Microbial World: Basidiomycota)
-Mark Dinicol

Commensalism -term used to describe a relationship between two living organisms where one benefits and the other is not significantly harmed or helped. (H.T. Baumgarten & K. Fiedler 1998. Parasitoids of lycaenid butterfly caterpillars). Some biologists argue that any close interaction between two organisms is unlikely to be completely neutral for either party, and that relationships identified as commensal are likely mutualistic or parasitic in a subtle way that has not been detected. (Benzing, D.H. 1980. Biology of the Bromeliads.)

The relationship of barnacles on gray whales is an example of commensalism
-Mark Dinicol
Enhancement = commensalism RSwite
A mutualistic relationship where one individual benefits while the other is neither harmed nor benefited. For example, the dung beetle relies on the scat of the gopher tortoise which it crafts into a ball and rolls to a location where it can be eaten later. ...
www.auburn.edu/academic/forestry_wildlife/longleafalliance/teachers/teacherkit/glossary.htm A mutualistic relationship where one individual benefits while the other is neither harmed nor benefited. For example, the dung beetle relies on the scat of the gopher tortoise which it crafts into a ball and rolls to a location where it can be eaten later. ...
www.auburn.edu/academic/forestry_wildlife/longleafalliance/teachers/teacherkit/glossary.htm Commensialism means literally 'at table together'. This is a symbiotic relationship between two species in which one species benefits and the other neither benefits or harms. Often, the host species provides a home and/or transportation for the other species. http://www.botany.uwc.ac.za/sci_ed/grade10/ecology/symbiosis/commen.htm

Endomycorrhiza: The mass of hyphae forming the body of a fungus, oomycete, or chytrid. Endomycorrhizae does not form a fungal sheath around the root like ectomycorrhizae does, but it penetrates the cortical cells but doesn’t penetrate the cell membrane- Travis Unsworth http://www.uwlax.edu/biology Biology of Plants 7th Edition

Endomycorrhizae are in soil fungi's which pernetrate plant root cells and increases both the plants and fungi's uptake of nutrients. This plant/fungi relationship is known as the mycorrhiza fungi. (Jackie Taylor)
http://www.nrp48.ch/projects/projects_detail.php?nfprojnum=17&isactdescr=yes Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. 266.

Hartig net - a complex network of fungal hyphae that is the site of nutrient exchange between the fungus and the host plant. (McGraw-Hill Dictionary of Scientific and Technical Terms 2003). It is formed in ectomycorrhizae by hyphae which grow between the cells of the root epidermis and cortex. The Hartig net eventually surrounds many of the cortical and epidermal cells. In the roots of most angiosperms colonized by ectomycorrhizal fungi, the epidermal cells are triggered to enlarge primarily at right angles to the surface of the root, thickening the root rather than extending it, and the Hartig net is confined to this layer. (Raven. Biology of Plants 2005.)

Diagram of typical ectomycorrhiza including the Hartig net, fungal mantle and external hyphae
- Mark Dinicol

Hyphae - long slender tubes that develop from germinated spores and form the structural parts of the body of a fungus. (Martinko J. 2005. Brock Biology of Microorganisms). In many species of fungi, hyphae are divided into sections by cross walls called septa. Each section contains at least one haploid nucleus, and the septa usually have perforations that allow cytoplasm to flow through the hypha. A large mass of hyphae is known as a mycelium, which is the growing form of most fungi. (The American Heritage Science Dictionary. 2005).

Hyphae of Penicillium
- Mark Dinicol
Enhancement (Hyphae): The vast majority of fungi are filamentous and the vegetative stage is a cylindrical thread-like filament called a hypha. Most hyphae are 2-10 um across, and cannot be resolved by the naked eye. The hyphal wall is quite tough, and composed of mainly of chitin (www.uoguelph.ca/~gbarron/MISCELLANEOUS/hyphae.htm). Hyphae contain nuclei, mithochondria, robosomes, Golgi and membrane-bound vesicles within a plasma-membrane bound cytoplasm (MicrobiologyBytes 2007, online). Tessa J Enhancement – Jessi.E.W There are three different types of hyphae which include generative hypha, skeletal hypha and binding hypha. If all three are present in the fungi then the fungi is termed polypore hyphae.

Host (AarenS)
A host is an organism that is being predated upon by a parasite, which is an organism that is dependant upon the host to live, grow, and multiply. A host in such a relationship does not benefit from the relationship, but is instead harmed by the parasite in various ways and can even be killed by the relationship it has with the parasite. Examples could be a tree or shrub acting as host to a mistletoe (parasitic plant from the order santalales seen below) which does not end until the death of either the host or the parasite, a human being bit by a mosquito which is a form of parasitism that does not last very long, or a vertibrate carrying a tape worm.
(Biology of Plants, 7th edition)
(http://www.science.siu.edu/parasitic-plants/)
Enhancement (Stephanie Lauer): a host is the larger participant in a symbiotic relationship, serving as a home and feeding ground to the symbiont (the smaller participant in the symbiotic relationship). Symbiotic relationships are classified as either mutualism, commensalism or parasitism. In mutualism both of the organims are benefit, in commensalism one organism benefits while the neither helping nor harming the other in any significant way and a parasitism mean one organism benefits at the cost of the other (Campbell & Reece, Biology 7th ed. pg 545)

Intracellular growth = RSwite Plant cells engage in mutualistic and parasitic endosymbioses with a wide variety of microoganisms, ranging from Gram-negative (Rhizobium, Nostoc) and Gram-positive bacteria (Frankia), to oomycetes (Phytophthora), Chytridiomycetes, Zygomycetes (arbuscular mycorrhizal fungi) and true fungi (Erysiphe, ascomycete; Puccinia, basidiomycete). Endosymbiosis is characterised by the 'symbiosome', a compartment within host cells in which the symbiotic microorganism is either partially or completely enclosed by a host-derived membrane. The analysis of plant mutants indicates that the genetic requirements for the interaction with rhizobia and arbuscular mycorrhiza fungi are partially overlapping. The extent to which plants use similar or identical developmental programs for the intracellular accommodation of different microorganisms is, however, not clear. For example, plant cells actively weaken their cell wall to facilitate bacterial colonisation, whereas penetration by fungal symbionts appears not to be assisted in this manner. Moreover, different transport requirements are imposed on the symbiotic interface of different interactions indicating that additional system-specific components are likely to exist. http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VS4-40NMR23-C&_user=10&_coverDate=08%2F01%2F2000&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=e5a654926bf1378c54faebda2d237828
Figure 1 Here is a piture showing how cells interact with one another when it
comes to intracellular growth and nutrient sharing. www.emc.maricopa.edu/.../BIOBK/waterflow.gif
RSwite

Mantle The mantle, or fungal mantle, is a sheath or net-like mesh of fungal hyphae that forms around roots. This sheath like fungus is generally ectomychorizae, and is comprised of mainly bacidiomycetes fungi, and less often ascomycetes fungi. Certain hormones are secreted by the fungi of the mantle that may cause the root to branch. (Raven, pg. 292-293) The hyphae of the inner mantle make up the hartig net, which is a complex nutrient transfer system between both cortex and epidermal cells. The fungal mantle increases the absorption of water and nutrients of the root system, benefiting the plant.( Mycorrhizas: Anatomy and Biology, Peterson, L., et.al. pg. 22,163) Jake
Enhancement (Nicole L) This is a picture of fungal mantle surrounding roots of a plant host
Image from ocid.nacse.org/.../bot461/imghtm/ectotips.htm

Mutualism The relation between two different species of organisms that are interdependent; each gains benefits from the other. A type of symbiosis where two (or more) organisms from different species live in close proximity to one another and rely on one another for nutrients, protectio, or other lif funcitons. Both (or all) of the organisms invloved benefit from the relationship. http://www.biology-online.org/dictionary/Mutualism a relationship between two organisms of different species that benefits both and harms neither. For example, lichens are a fungus and an alga living in mutualism: The fungus provides a protective structure, and the alga produces a carbohydrate as food for the fungus. http://encarta.msn.com/dictionary_/mutualistic.html R.Swite
Enhancement: Amanda Last Mutualism: association between organisms of two different species in which each is benefited. Mutualistic arrangements are most likely to develop between organisms with widely differing living requirements. The partnership between nitrogen-fixing bacteria and leguminous plants is an example, as is the association between cows and rumen bacteria (the bacteria live in the digestive tract and help digest the plants eaten by the cow). The associations between tree roots and certain fungi are often mutualistic.(Britannica Online Encyclopedia). The relationship existing between two organisms of different species which contribute mutually to each other's well-being; an instance of this.(Oxford English Dictionary).
Enhacement:

As seen in the picture, mycorrizal fungi benefits the plant by increasing its absorbance surface area.It is benafitted by food it obtains from the plant.Both cannot live properly without each other.
(Plant Health Care.co.uk,http://www.planthealth care.co.uk/images/fungi.gif)
(Raven, Biology of plants, pg. 291)
Jake

Mycelium: Mass of hyphae that constitutes the vegetative part of a fungus. The mycelium makes up the thallus, or undifferentiated body, of a typical fungus. It may be microscopic in size or developed into visible structures, such as brackets, mushrooms, puffballs, rhizomorphs http://cancerweb.ncl.ac.uk/cgi-bin/omd?mycelium http://www.britannica.com Travis Unsworth

Enhancement (Andrea Chapman) Armillaria root rot (Armillaria ostoyae) is a common fungus found in British Columbia’s forests that is easily identifiable by its mycelial fans. These fans are a white/creamy colour and found under the bark at the base of the stump and roots (Cruickshank et al. 1997).

Cruickshank M.G., Morrison D.J., and Punja Z. K. 1997. Incidence of Armillaria species in precommercial thinning stumps and spread of Armillaria ostoyae to adjacent Douglas-fir trees. Canadian Journal of Forest Research 27: 481-490
Enhancement (Nick N) This is a picture of mycelium growing on a decomposed log.www.ipm.iastate.edu/.../2006/4-5/fungi.html

Parasite: A parasite is something that lives in dependence of another organism in order to maintain its existence. These organisms do not give back to the host that they feed from. Instead they usually cause harm, but rarely do they kill the host. The parasite has to be in its host to live, grow and multiply. A common, well-known type of a parasite is a hookworm. Hookworms can be commonly found in mammals, most commonly humans and domestic animals. Hookworms attach themselves in the lining of the small intestine, and cause diseases, and malnutrition as well, as they eat the nutrients and keep them from going to the host.

Fig.1: a common parasite, the hookworm. Found in the small
intestine of humans and their domestic animals.
References: http://student.biology.arizona.edu/honors98/group15/whatisaparasite.htm
http://www.m-w.com/dictionary/parasite
http://phil.cdc.gov/phil/home.asp
Public Health Image Library] Image #5205

-Scott Horley
Parasite (enhancement) - Parasites that live inside the live body of the host are called endoparasites (e.g., hookworms that live in the host's gut), and those that live on the outside are called ectoparasites (e.g., some mites). (Zimmer, Carl 2001. Parasite Rex) .Many endoparasites acquire hosts by gaining entrance to their tissue; others enter the host when it consumes certain raw foods. Ectoparasites, on the other hand, often have elaborate mechanisms and strategies for finding hosts. Some aquatic leeches, for example, locate hosts by sensing movement and then confirm their identity through skin temperature and chemical cues before attaching. (The American Heritage® Science Dictionary)

Mites parasitising a harvestman
- Mark Dinicol

Pathogen
Pathogen: An agent of disease. A disease producer. The term pathogen most commonly is used to refer to infectious organisms. These include bacteria, viruses , and fungi. Less commonly, pathogen refers to a noninfectious agent of disease such as a chemical. http://dendroglossary.wetpaint.com/page/Symbiotic+Associations%3B+Mycorrhial+Fungi+and+Mycorrhizae A disease producing organisms that can exist in many different places. (for example: air, dust, counter top surface, the body, etc.) A pathogen or infectious agent is a biological agent that causes diseaseor illness to its host. The term is most often used for agents that disrupt the normal phisiology of a multicellular animal or plant. however, pathogens can infect unicellular organisms from all of the biological kingdoms. http://www.biology-online.org/dictionary/Pathogens R.Swite

www.scielo.br/img/fbpe/fb/v27n4/a17fig01.gif
A picture showing the effects that some pathogen have on trees.R.Swite Enhancement: Pathogens are identified by the hosts they infect and the symptoms they cause; it is also important to identify the specific properties of the pathogen that contribute to its infectious capacity—a characteristic known as virulence. http://www.britannica.com/eb/article-216178/microbiology Travis Unsworth

Rhizoshere:
The Rhizosphere is the area that surrounds the roots of plants. The Rhizosphere is directly influenced by the root’s secretions, the soil microorganisms and the soil itself. The root of the plant and the biofilm of the root can greatly influence the soil. The Rhizosphere can change the soils pH and nitrogen transformations by crowding the bacteria from the sloughed-off plant cells as well as the proteins and sugars the root releases.

Ref:
http://www.regional.org.au/au/allelopathy/2005/2/3/2535_fujiiy.htm?print=1
http://uwstudentweb.uwyo.edu/T/Twhite/

-Scott Horley Enhancement = rhizosphere RSwite The soil zone that surrounds and is influenced by the roots of plants. Within the rhizosphere, roots secrete a slimy lubricating substance, called mucigel, that cause the particles of soil to adhere to the roots, assisting in the uptake of water, and encourages the growth of nitrogen-fixing bacteria and other beneficial microorganisms. http://www.thefreedictionary.com/rhizosphere...The area immediately surrounding plant roots that is responsible for creating the conditions of this micro-habitat when taking into account the properties and actions of the plant. http://www.biology-online.org/dictionary/Rhizosphere RSWITE

Saprophyte: An organism, that obtains food by breaking down organic matter into simple compounds and absorbs nutrients from those compounds. Saprophytes include mainly fungi and bacteria, but also include molds, actinomycetes, and a select few plants and animals. (Ryan T)
http://www.bookrags.com/research/saprophyte-enve-02/ (para1
http://dictionary.reference.com/browse/Saprophyte (def #'s 2 & 5)

Enhancement –Saprophyte decomposing dead wood. fungifest .com Jessi.E.W
Enhancement = Saprophyte RSwite Any plant growing on decayed animal or vegetable matter, as most fungi and some flowering plants with no green color, as the Indian pipe. http://dict.die.net/saprophyte/ An organism, especially a fungus or bacterium, that grows on and derives its nourishment from dead or decaying organic matter. http://www.answers.com/topic/saprophyte?cat=health

Symbiosis Meaning derived from the Greek word symbiosis meaning “a living together”. (Online Etymology Dictionary, http://dictionary.reference.com/browse/Symbiosis) This term is used to describe a close association, or bond between two or more organisms of different species, often but not always benefiting each partner. An example of a symbiotic relationship is of Lichen (fungi) and Bacteria. (The American Heritage® Science Dictionary.) http://dictionary.reference.com/browse/Symbiosis) There are four types of symbiotic relationships, Mutualism, (which is a mutually beneficial relationship where each is dependent on other organism), Commensalism , (not a dependent relationship, but is mutually beneficial), Paratism, (where a parasite is dependent on its host, but harms it in the process), and amensalism,(much like parasitism: a relationship where one organism is benefited and the other is inhibited or harmed). (The American Heritage® Science Dictionary, http://dictionary.reference.com/browse/Symbiosis)( Online Etymology Dictionary, http://dictionary.reference.com/browse/Symbiosis) Jake

Enhancement: By Conyr A.
This photo shows a symbiotic relationship between a young tree and a fully developed tree. In this case it would be considered an amensalism relationship because only the smaller tree benefits from growing off the developed one. (Image from: istockphoto.com at the address http://www1.istockphoto.com/file_thumbview_approve/190375/2/istockphoto_190375_symbiosis.jpg)

Zygomycete (Caitlin Deas)
A fungus, such as bread mold, that lives on organic matter or as a parasite, in the ClassZygomycetes. (Encarta)
http://encarta.msn.com/dictionary_561563378/zygomycete.html Zygomycetes have hyphae that are continuous tubes, without cross-walls. They are one of two major groups of the aseptate fungi (the other group is the chytrids).
(Nature Navigator)
http://internt.nhm.ac.uk/jobj/runjava.jobj?java=ctol.CTOLServer&method=printNamePage&accountref=987&NAMEID=27087

Below are two examples of zygomycetes. The first is Pilaira anomala on deer feces. The second is Phycomyces blakesleeanus

(Cornell Mushroom Blog)
http://hosts.cce.cornell.edu/mushroom_blog/index.php?paged=3

(JGI)
http://genome.jgi-psf.org/Phybl1/Phybl1.home.html

Enhancement: Terrestrial saprobes or parasites of plants, animals, or humans; asexual reproduction by aplanospores (nonmotile spores) in sporangia or by conidia; sexual reproduction by fusion of morphologically similar gametangia, sometimes differing in size, resulting in thick-walled zygospores. (Encyclopedia Britannica Online, http://www.britannica.com/eb/article-57977/fungus ). Lee Williams.

Compare and Contrast (first word alphabetical)
Arbuscule/Mantle An arbuscule is a hypha that penetrates a roots cornical cell, and froms a tree- like web around the cortex. The Fungal mantle surrounds s the outside of the tree root in a sheath like mass of fungal hyphae. Both fungi help in the absorption of water and nutrients and transfer them to the trees roots. Both structures “surround” organ and transfer substances. They differ in that the arbuscule penetrates a cell, and the mantle surrounds the outside. An arbuscule is endomycorrhizea, formed of around 200 species of zygomycotic fungi and live in 80% of vascular plant roots; whereas, the mantle, which is ectomycorrhizea, is generally made of bacidiomycetes or ascomycetes fungi, and are generally found on the roots of certain groups of trees and shrubs, and are generally quite species specific. There are around 5000 species of fungi in ectomycorrhizal associations. (Raven, pg. 292-293) An arbuscule, or endomycorrizal fungi is dependent on a host cell and cannot by cultured on its own, whereas the mantle fungi can be cultured on its own. (Mycorrhizas: Anatomy and Biology, Peterson, L., et.al. pg. 163) Jake
Ascus/Ascospore (Dennis Murengi) Ascus: A specialised cell, characteristic of the ascomycetes, in which two of the haploid nuclei fuse to produce a zygote that immediately divides by meiosis; at maturity, an ascus contains ascospores. (Biology of Plants 7th Edition G-3) Ascospore: A spore produced within an ascus; found in ascomycetes. (Biology of Plants 7th Edition G-3) Both the ascus and ascospore are found in a type of fungi called ascomycetes. (Biology of Plants 7th Edition, Pg 271) However ascus and ascospore differ in their structure. The ascus has a saclike structure while the ascospores are spores formed inside the ascus. (Biology of Plants 7th Edition, Pg 271)

The image above shows an ascus which contains ascospores. (www.tolweb.org) http://www.tolweb.org/Ascomycota

Ascomycete/ Ascospore: Ascomycete: any of a subdivision (Ascomycotina) of fungi, including the mildews, yeasts, and truffles, that produce spores in asci; sac fungus. www.yourdictionary.com/ascomycete Ascospore:


	A sexual spore from certain fungus species in which spores are found in a sac called an ascus. Haploid spores found in the asci of Ascomycete fungi.

www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-A/ascospore.html Ascomycete and ascospores both exist in fungi while ascospores are the product of ascomycete. (Matti Harper)

Ascomycete/Ascus: An ascus is a saclike structure containing ascospores and usually borne in a fungal fruiting body (APSnet, Plant Pathology Online). Asci are produced by fungi of the class Ascomycetes (Encyclopaedia Britannica, Online). An ascospore is a sexual spore from certain fungus species in which spores are found in a sac called an ascus. Haploid spores found in the asci of Ascomycete fungi (Merriam-Webster’s Dictionary, Online). There are eight such spores in each ascus. The ascospores are released in the atmosphere when slight fluctuations of the relative humidity cause a rupture in the top extremity of the asci (Institut National de la Recherche Agronomique, Pathology). Tessa J

Ascomycetes and Basidiomycetes - species belonging to the two large phyla Basidiomycota and Ascomycota, which together comprise the subkingdom Dikarya, also refered to as the "Higher Fungi" within the Kingdom Fungi. (Moore, R.T. (1980). "Taxonomic proposals for the classification of...). Basidiomycota include mushrooms, puffballs, stinkhorns, bracket fungi, other polypores, jelly fungi etc. They are filamentous fungi composed of hyphae and reproduce sexually via speicalized end cells, however some can reproduce asexually. Ascomycota are commonly known as the "Sac Fungi", with some familiar examples being morels, truffles, Baker's yeast, cup fungi, and the majority of lichens. When reproducing sexually, they produce nonmotile spores in a distinct cell called an "ascus". However, some do not reproduce sexually. (John W. 1996. "Ascomycota", Tree of Life).

Some examples of basidiomycetes. Scarlet Elf Cap growing on oak twigs is an example of an acomycetes.

- Mark Dinicol
Ascomycete / zygomycete: Ascomycete are fungus in the phylum Ascomycota characterized by the presence of sexually produced spores formed within an ascus. The nature of hyphae is Septate, their method of asexual reproduction is by budding, conidia(nonmotile spores) and fragmentation and their type of sexual spore is an ascospore.Some common plant diseases cause by ascomycete are powdery mildew, brown rot of stone fruits, chestnut blight and Dutch elm disease. Zygomycete are fungus from the Zygomycota phylum. The nature of hyphae is aseptate and coenocytic, method of asexual reproduction is nonmotile spores(sporangiospores), the type of sexual spore is a zygospore(in zygosporangium), and they cause soft rot of various plant parts. (http://www.thefreedictionary.com/ascomycete) (Biology of Plants P. 263)

-VanessaV

Ascospore/Basidiospore (Jessica Wrench)

Ascospore- “A spore produced within the ascus; found in ascomycetes.” (Biology of Plants 7th ed. Peter H. Raven, Pg. G-3)
Basidiospore- “A spore of the basidiomycota, produced within and borne on a basidium following nuclear fission and meiosis. Also called and basidiocarp.” (Biology of Plants 7th ed. Peter H. Raven, Pg. G-3)

Ascospores and basidiospores are similar in that they are both spores produced by fungi. These two spores differ in where they are produced and released. The basidiospores are produced by a fungus called Basidiomycete. These spores are discharged from the fungi and once they germinate they produce hypheae which grow out in a circular manner from the original spore. The ascospores are produced by a fungus known as ascomycetes. Due to the processed of meiosis, each ascus will contain eight ascospores.

This is a photo of a species of ascomycetes that is responsible for the release of Ascospores.

Photo found: http://www.clarku.edu/faculty/dhibbett/TFTOL/images/fungi/suIllusstictus.jpg

This is a photo of a Basidiomycete fungus that is responsible for the release of Basidiospores.

Photo found: http://bugs.bio.usyd.edu.au/Mycology/images/Topics/Feeding/Basidiomycete1.jpg
Basidiospore/Basidium
Basidiospore: A sexually produced fungal spore borne on a basidium in the fungi known as basidiomycetes. Basidiospores are produced by the union of the nuclei at the tip of a binucleated segment of a hypha. The resulting zygote then divides by meiosis into four haploid nuclei, each of which migrates to the very tip to be released as a basidiospore. A typical mushroom produces billions of basidiospores. www.thefreedictionary.com/basidiospore Basidium: A small, specialized, club-shaped structure typically bearing four basidiospores at the tips of minute projections in the fungi known as basidiomycetes. The basidium is unique to basidiomycetes and distinguishes them from other kinds of fungi. www.thefreedictionary.com/basidium Both the basidiospore and the basidium are both parts of fungi. The basidiospores are attached to the basidium but serve a different purpose.(Matti Harper)

Basidium/Ascus Basidium:
Club-shaped reproductive cell of the fungal family basidiomycota. Each basidium produces 4 basidiospores through meiosis and nuclear fisson. The basidiospores are borne on stalk-like structures called stigmata. (Raven, 7th ed.)

Ascus:

Site of spore formation in ascomycetes. The ascus is a saclike cell that bursts at maturity releasing eight ascospores. Asci are formed at the tips of hyphae on the inner layer of a structure called the ascoma. (Introductory Mycology. Alexopoulos, C.J. and Mims, C.W., 1979)

Basidia and asci are alike in that they are both the site of spore formation in fungi. They are different in that they produce different numbers of spores, four are produced by basidia and eight are produced by asci. They also differ in their shape, basidia are club-shaped while asci saclike structures. Katherine Loewen

Commensalism/Mutualism
Commensalism a relationship between two living organisms where one benefits and the other is not significantly harmed or helped. It is derived from the English word commensal, meaning the sharing of food. An example of commensalism would be epiphytic plants, which depend on a larger host plant for support but which do not derive any nourishment from it.
Mutualism is a biological interaction between individuals of two different species, where both individuals derive a fitness benefit. Similar interactions within a species are known as cooperation. Mutualism may be classified in terms of the closeness of association, the closest being symbiosis, which is often confused with mutualism. One or both species involved in the interaction may be obligate, meaning they cannot survive in the short or long term without the other species. Many plants will function in a voluntary mutualistic relationship as companion plants, providing each other with shelter, fertilization, the repelling of pests, etc. For example, beans may grow up cornstalks as a trellis, while fixing nitrogen in the soil for the corn. Also, the relationship between bees and flowers would be considered mutualistic. The bees get nectar for a food source and the flowers get pollinated so they can reproduce.
http://en.wikipedia.org/wiki/Commensalism
http://en.wikipedia.org/wiki/Mutualism
http://dictionary.reference.com/browse/Commensalism
Krista Neufeld

Ectomycorrhiza/Endomycorrhiza (Jackie Taylor)
Endomycorrhiza: An in soil fungi which penetrates plant root cells. Endomycorrhizae does not form a sheath around the root tip, but does penetrate the root cells. This plant/fungi relationship is known as the mycorrhiza fungi. The fungus is made up of highly branched hyphae.
Ectomycorrhiza: Forms a sheath around the root tip of a plant. A Hartig Net is than formed by the fungus, meaning an inward growth of hyphae penetrates the plant root. The fungus gains carbons and other organic substances from the plant and in return helps the plants take up nutrients and water. It also puts up a defense against parasites and other predators. The fungus mainly infects woody plants and is the type used in most reforestation efforts.
Both funguses’ increases: nutrient uptake, drought resistance, growth rate and protection against some fungal root pathogens in the plant.
Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. 266.
NC State University -http://www.cals.ncsu.edu/course/pp318/profiles/myc/mycorrhizae.htm#endomycorrhizae
Northern Ireland Fungus Group - http://www.nifg.org.uk/ecto.htm
Enhancement:
Ectomycorrhiza is formed usually of Basidiomycetes fungi, and sometimes of Ascomycetes fungi, whereas Endomycorrhiza is formed of Zygomycetes fungi.(Raven, Biology of Plants, pg. 291)
Jake

Epigeous/Hypogeous: (Jackie Taylor) Epigeous – A form of seed germination where the cotyledons are carried above ground level. Ie: Onions, Honeylocust Hypogeous – Form of seed germination where the cotyledons remain underground. They remain underground because elongation occurs above the cotyledon. Ie: Peas, Oaks, Kentucky coffeetree
This photo shows the epigeous germination on the left in the Honeylocust and the hypogeous germination on the right in the Kentucky coffeetree.
University of Kentucky Horticulture - http://www.uky.edu/Ag/Horticulture/kytreewebsite/Propagation/schoolprojects/seedling%20emergence%20project.htm Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. 506-507
Fungus/Lichin Fungus: Any of a group of unicellular, multicellular, or syncytial spore-producing organisms feeding on organic matter, including moulds, yeast, mushrooms, and toadstools. Lichen: Any plant organism of the group Lichens, composed of a fungus and an alae in a symbiotic association, usually of green, grey,or yellow tint and growing on and colouring rocks, tree trunks, roofs, walls,etc.

Heterotroph/ Saprophyte: A heterotroph is an organism that cannot manufacture organic compounds and so must feed on organic materials that have originated in other plants and animals (Raven, Biology of Plants).It is a creature that must ingest biomass to obtain its energy and nutrition. An example of a heterotroph is a human being. Even a few vascular plants are heterotrophic, parasitizing the roots of other plants and thereby obtaining their own nourishment. These plants are known as saprophytes (Science Encyclopedia, Vol 3, Online).A saprophyte is any plant that depends on dead plant or animal tissue for a source of nutrition and metabolic energy. Most do not produce chlorophyll and therefore do not photosynthesize; they are dependent on the food energy they absorb from the decaying tissues, which they help to break down. An example of a saprophyte is mold (The Columbia Encyclopedia, Sixth Edition 2007 Online). A saprophyte is an organism that secures its food directly from nonliving organic matter (Raven, Biology of Plants). Tessa J

Hartig Net/Mantle: (Jackie Taylor) Hartig Net: A highly branched network that surrounds many of the cortical and epidermal cells. Hartig net functions as the interface between the fungus and the plant. It is formed as hyphae from the fungus penetrate the root along the middle lamellae between the root cortical cell walls. Mantle: A sheath of hyphae that covers the root surface. Secretes hormones which cause the root to branch. Both the hartig net and the mantle are produced by the ectomycorrhizae. They involve creating a sheath/covering of hyphae. They differ in that the mantle covers just the root and secrets hormones and the hartig net surrounds the cortical and epidermal cells.
Site name: Ectomycorrhizae information from Smith and Read 1997, Molina, Massicotte and Trappe 1992, Harley and Smith 1983 - http://botit.botany.wisc.edu/courses/mpp/Ectomyco116.html

Host and Parasite - Parasitism is a phenomenon in which two organisms co-exist over a prolonged period of time, usually the lifetime of one of the individuals. A host is an organism that harbors a virus or parasite, typically providing nourishment and shelter. (Centers for Disease Control and Prevention (2004). The Influenza (Flu) Viruses). A parasite, usually physically the smaller of the two, is an organism that lives on the host and derives nutrients from it; the association is beneficial to the parasite and harmful to the host. (Raven. Biology of Plants). An example of this relationship is varroa mites and bee colonies. The mites are the parasites - the beneficial ones, and the bees are the hosts, having their colonies weakened and destroyed by the mites.

LTSEM Microscope image of Varroa mite destructor on a honey bee host.
- Mark Dinicol

Hyphae/Mycelium: Hyphae are the tiny individual filaments that compose a fungus. Hyphae are composed of tubular cell walls surrounding the plasma membrane and cytoplasm of the cells. Hyphae have cell walls composed of chitin, a nitrogen-containing polysaccharide. (Campbell Reece, 7th Edition, pg. 609) Mycelium is the term for the interwoven mass that the hyphae create as they grow. (Raven, G-15) Basically, mycelium is the term we use to refer to the body of the fungus, which is made up of all the interwoven hyphae. Hyphae makes up mycelium, and mycelium is the collective term for all the hyphae.
Amanda M.

Mutualism/Parasite
Mutualism is an interaction between individuals of different species and plays a large role in ecology. This interaction is characterized by the benefit of both species from the relationship, and the increase in their survivorship. One example of this mutualistic relationship is bees and flowers, the bees gather the pollen and as they travel from flower to flower they pollinate them. A flower gets its pollen passed from one individual to another. In turn the flower provides a food reward in the form of nectar, or pollen as a solid food source. A parasite is an organism that may not be closely related to the host organism, but they co-exist indefinitely until one of the organism dies. The parasitism is characterized by one organism (usually the smaller organism) benefits from the host organism that is harmed by the relationship. An example of this parasitic relationship is the hookworm which lives in the intestine of its host, usually a cat or dog. http://www.aber.ac.uk/~mpgwww/Edu/EduIndex.html Begon, M., J.L. Harper and C.R. Townsend. 1996. Ecology: individuals, populations, and communities, Third Edition. Blackwell Science Ltd., Cambridge, Massachusetts, USA. Mike Tomlinson
Enhancement:
Parasitism is a symbiotic relationship where one organism is dependent on the other, but harms its host in the process. It is similar to amensalism, but with amensalism the visitor organism is not necessarily dependent on the host. In contrast, in a true mutualistic sybiotic relationship, both species are dependent on each other, and benefit each other.(The American Heritage® Science Dictionary, http://dictionary.reference.com/browse/Symbiosis)
Jake
Mutualism / Lichen; Lichen – the symbiotic relationship formed by mutualistic association between a fungus and a photosynthetic algae or cyanobacterium (Campbell & Reece, Biology 7th ed. Glossary). Mutualism – a symbiotic relationship in which both participants benefit (Campbell & Reece, Biology 7th ed. Glossary). Lichens are a symbiotic association of millions of photosynthetic microorganisms held in a mass of fungal hyphae, meaning the fungal component is usually an ascomycete and the photosynthetic partner is usually a unicellular or filamentous green algae or cyanobacteria (Campbell & Reece, Biology 7th ed. Pg 621). These structures are involved in the transfer of carbohydrates and nitrogen compounds from the photobiont (the photosynthetic compound of the lichen) to the fungus (Raven, Biology of Plants, pg 290). In english terms, this means that lichen need mutualism with a fungus and a photosynthetic microorganism to live and survive. Stephanie Lauer
Mutualism/Symbiosis (Dennis Murengi) Mutualism: The living together of two or more organisms in an association that is mutually advantageous. (Biology of Plants 7th Edition G-15) Symbiosis: The living together of in close association of two or more dissimilar organisms; includes parasitism (in which the association is harmful to one of the organisms) - Biology of Plants 7th Edition G-23) Both mutualism and symbiosis are similar in that they both involve an association between two or more organisms. However the two relationships differ in that mutualism is a type of symbiosis in which both or all of the organisms involved benefit from the relationship. (www.biology-online.org) http://www.biology-online.org/dictionary/Mutualism Symbiosis on the other, hand also includes parasitism, which is a one-sided relationship whereby one of the symbionts (the parasite) benefits at the expense of the other (the host). (www.eden.rutgers.edu) http://www.eden.rutgers.edu/~tavisa/Symbiosis.html
Mycelium/Mycorrhiza Mycelium: The mass of fine branching tubes (known as hyphae) that forms the main growing structure of a fungus. Visible structures like mushrooms are reproductive structures produced by the mycelium. www.thefreedictionary.com/mycelium Mycorrhiza: The symbiotic association of the mycelium of a fungus with the roots of certain plants, such as conifers, beeches, or orchids. www.answers.com/topic/mycorrhiza Mycorrhiza is the relationship between mycelium and the roots of other plants. (Matti Harper)

Mycorrhizae/Lichen
Mycorrhizae:
Mycorrizhae are a mutually beneficial relationship between the roots of vascular plants and fungi. Nearly all higher plants exhibit this relationship and when are grown without fungi they experience malnutrition and often die. In this relationship the plants benefit through increased uptake of water and nutrients and protection from pathogens while the fungus benefits through transfer of carbohydrates from the plant. (Jennings, D.H. and Lysik G., 1996) and (Freeman 2004)

Lichen:
Lichen are a relationship between a fungus and a green algae or a cyanobacteria. In this relationship the fungus is called the mycobiont and the algae or cyanobacteria is called the photobiont. The fungus and the photobiont are connected by hyphae from the fungus that penetrate the cells of the photobiont, through which the fungus obtains carbohydrates and nitrogen. The photobiont also benefits from this relationship because it is provided with and ideal place to grow. (Freeman 2004)

Lichen and Mycorrhizae are similar in that they are both examples of mutualistic relationships. A mutualistic relationship is when two or more organisms live together in a situation through which they both benefit. They are also similar in that the fungi in both relationships obtains carbohydrates from the other organism. A difference between lichen and mycorrhizae is that mycorrhize are an associaton between a fungus and a plant while a lichen is a relationship between an algae or a cyanobacteria and a fungus.
Katherine Loewen

Mycorrhiza/Parasite (AarenS)
A parasite is an organism that lives in or on a member of a different species and derives nutrients from it, this relationship is beneficial to the parasite and harmful to the host. (Biology of Plants, 7th edition).

A mycorrhiza is a fungus which attaches to the roots of a host of a different species (a tree in this case) and enters a relationship with the host that is beneficial to both the host and the fungi. In this relationship the host provides nutrients in the form of sugars to the fungi, and the fungus provides an increase of surface area which the tree uses to absorb a greater amount of water and nutrients.

Parasites and mycorrhiza are similar in that they both have evolved to be dependant on another organism in order to live and reproduce. Parasites and mycorrhizae differ because while the parasitic relationship benefits only the parasite and harms the host, the mycorrhiza has entered a relationship which is beneficial to both organisms.

Mycorrhiza/Root Hairs
Mycorrhiza: A symbiotic association between certain fungi and plant roots; characteristic of most vascular plants. These symbioses are characterized by bi-directional movement of nutrients where carbon flows to the fungus and inorganic nutrients move to the plant, thereby providing a critical linkage between the plant root and soil. In infertile soils, nutrients taken up by the mycorrhizal fungi can lead to improved plant growth and reproduction. As a result, mycorrhizal plants are often more competitive and better able to tolerate environmental stresses than are nonmycorrhizal plants.
Root Hairs: A tiny extension of a root epidermal cell, growing just behind the root tip and increasing the surface area for absorption of water and minerals. It is a delicate structure, which survives for a few days only and does not develop into a root. Root hair cells are found just behind the root tip where they are continually being formed. They grow out into the soil for a few millimetres to produce the root hair. Each root hair is made of a single cell. At the root tip mitosis cell division is very active making new cells for growth to replace the root hair cells that die.
Mycorrhiza/Zygomycete Mycorrhiza: A symbiotic association between certain fungi and plant roots; characteristic of most vascular plants. These symbioses are characterized by bi-directional movement of nutrients where carbon flows to the fungus and inorganic nutrients move to the plant, thereby providing a critical linkage between the plant root and soil. In infertile soils, nutrients taken up by the mycorrhizal fungi can lead to improved plant growth and reproduction. As a result, mycorrhizal plants are often more competitive and better able to tolerate environmental stresses than are nonmycorrhizal plants. Zygomycete: a fungus (i.e. bread mold) that lives on organic matter or as a parasite. The most common members of the Zygomycota are the fast growing members of the Mucorales. They function as decomposers in soil and dung, thereby playing a significant role in the carbon cycle.

Parasite/Pathogen
Parasite: A parasite is an organism that lives in or on another organism, its host. A parasite is dependent on the host for nourishments and life functions. A parasite usually causes some harm to the host. Two examples of plant species that parasitize on other plants include, mistletoe and parasitic dodder. (MSN Encarta: Online )
Pathogen: A pathogen is a living microorganism that uses another organism, a host, for nourishment, causing illness and disease. Pathogens include various types of bacteria and fungus. (Biology Online org) A parasite and a pathogen share a similar relationship with another organism, or host, using it to obtain nourishment.

The difference between a pathogen and a parasite is the outcome they cause on the host. A parasite causes harm compared to the pathogen that can infect, causing disease or illness.

References: Biology Online Org. Website found: http://www.biology-online.org/dictionary/Pathogens
MSN Encarta:Online. Website found:http://encarta.msn.com/encyclopedia

- Nikki Heim.
Parasite vs. Saprophyte Parasite is an organism that lives on or in the host of a different species. This relationship is harmful to the host because the parasite derives some or all of its nutreints from the host. Saprophyte is an organism that lives on dead organic matter. Both parasites and saprophytes may harm their host. A saprophyte may decay the heartwood of a tree which would weaken the strength of the tree. A parasite may not decay the tree but it will weaken the tree by consuming the nutrient that the tree is manufacturing.
Jessi.E.W
Parasite/Symbiosis
Parasite: An organism that lives on or in a different kind of organism, the host from which it gets some or all of its nourishment. Parasites are generally harmful to their hosts (Raven Glossary. p.16), although the damage they do ranges widely from minor inconvenience to debilitating or fatal disease.
Symbiosis: Symbiosis is a close ecological relationship between the individuals of two or more different species. Sometimes a symbiotic relationship benefits both species, sometimes one species benefits at the other's expense, and in other cases neither species benefits. This relationship includes parasitism and mutualism (advantageous to both) (Raven Glossary. p.23). Parasite is harmful to the host, whereas symbiosis generally benefits the host. Rarely, the symbiosis relationship can be harmful to the host. Tamiki N
http://www.thefreedictionary.com/parasite, http://www.cals.ncsu.edu/course/ent591k/symbiosis.html

Germination and Primary Growth in Roots

DennisMurengi — Thu, 29 Nov 2007 17:33:21 CST

Adventitious roots (Dennis Murengi)
Anticlinal wall - Tyler Parnall
Apical meristem
Casparian strip- Liz Foster
Cortex
Endodermis
Epidermis- Jessi.E.W
Exodermis - Jackie Taylor
Feeder roots - Amanda Miller
Fibrous root system - Kevin Christie
Frankia
Germination - Krista Neufeld
Ground meristems- Nicole L.
Hypocotyl
Imbibition - Tori Waites
Lateral meristem
Meristematic region-Danielle Dorink
Mucigel
Mycorrhizae-Danielle Dornik
Nitrogen fixation - Russ Fountain
Periclinal wall
Pericycle
Primary meristems
Primary phloem (Dennis Murengi)
Primary xylem - Tyler Parnall
Procambium
Promeristem - Morgan Traverse
Protoderm - Kirsten Jorgensen
Protophloem - Kristie S
Protoxylem - Stephanie Lauer
Radial wall
Radicle - Amanda Miller
Rays
Root hairs
Root nodules - Kevin Christie
Stele
Suberin
Tap root system
Transverse wall
Turgor pressure - Tori Waites
Vascular cambium

Definitions (in alphabetical order)
Adventitious roots (Dennis Murengi) - A root that grows from somewhere other than the primary root, for example, from stems or leaves. (www.en.mimi.hu) http://en.mimi.hu/gardening/adventitious_roots.html Most commonly, adventitious roots arise out of stems, originating via cell divisions of the stem cortex or less often from auxiliary buds hidden in the bark. In some plants plant leaves are encouraged to form adventitious roots. Examples include: adventitious roots of a palm and of an aquatic plant that has unattached roots in moving water. (www.botgard.ucla.edu)
http://www.botgard.ucla.edu/html/botanytextbooks/generalbotany/typesofroots/index.html

The image above shows adventitious roots growing from the stem of a plant. (www.lexic.us)
http://www.lexic.us/definition-of/adventitious_root
Casparian Strip: The casparian strip is a band of primary cell walls that contain suberin (which is a fatty substance) on the anticline walls of the endodermal cells that stop water and minerals from seeping in between the cells and therefore forces the water and minerals to enter the endodermal cells and therefore be filtered before it enters the vascular cylinder. The main component in the casparian strip, suberin is named after the cork oak, as suberin is also found in cork. The casparian strip is named after the 19th century German scientist that discovered it, Robert Caspary.

http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/Bio%20102/Bio%20102%20lectures/Plant%20Structure/plant%20structure.htm (Clinton Community College), http://www.daviddarling.info/encyclopedia/C/casparian_strip.html (David Darling Encyclopedia), http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-C/Casparian_strip.html (Northwestern)
Liz Foster
Enhancement- A band like region of primary wall containing suberin and lignin. It is found in anticlinal-radial and transverse-wall of the endodermal and the exodermal cells. Only angiosperms have casparian strips in the exodermis.-Danielle Dornik
(Biology of Plants, 7th edition, Peter H. Raven G-4)

Endodermis – endo meaning inner dermis meaning skin The endodermis is a thin layer of cells bounding the stele and separating it from the cortex. The cells, surrounds the central core of the vascular tissue, and which helps to regulate the flow of water and dissolved substances. The endodermis is one of the most important adaptations of terrestrial plants. (Encyclopaedia Britannica and Merriam-Webster)

www.apsnet.org www.botany.hawaii.edu/
Enhancement:
Cells in the endodermis are waterproof and fit together very tightly with no intercellular spaces. These features allow the endodermis to be a highly effective barrier between vascular tissue and other cells. (Plant anatomy laboratory: http://www.sbs.utexas.edu/mauseth/weblab/webchap3par/3.4-2.htm). Katherine Loewen
Exodermis: (Jackie Taylor) The outer layer, one or more cells in depth, of the cortex in some roots; these cells are characterized by Casparian strips within the radial and transverse walls. The exodermis is located just below the epidermis.It is developed from the outermost layer or layers of cells of the cortex. The majority of angiosperm roots also have an exodermis with a Casparian stripes. Following development of Casparian strips, a suberin lamella is deposited on all walls of the exodermis. The exodermis reduces water loss for the root to the soil and provides a defense against attack by microorganisms. Under stress the exodermis develops closer to the root tip.
Enhancement (Exodermis) Russ Fountain
Below is a picture of a Smilax (greenbrier) root. Note the distinctive endodermis. The outermost layer of the cortex is differentiated as an exodermis, similar in appearance and function to the endodermis.
(“Roots play a vital role in plants, which is to take up water and nutrients from the soil.” - http://www.northern.edu/ramsayj/etechWeb/roots.htm)

(Springer Link - http://www.springerlink.com/content/3rehrkkwy3k1g1b1/) (http://trc.ucdavis.edu/biosci10v/bis10v/week8/casparian.gif)
(Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-9)

Feeder roots: Fine roots that activly take up water and minerals through root hairs, they are generally found within the top meter of soil. (The American Heritage Science Dictionary By Houghton Mifflin Company http://books.google.com/books?id=yKUagx8PB_EC&pg=PA544&lpg=PA544&dq=feeder+roots+dictionary&source=web&ots=KYqoT9BVK0&sig=mXMISi51qOMxEKcQhXwUFdJYsp8#PPA544,M1
Feeder roots have a symbiotic relationship with mycorrhizal fungi, the fungi are attached to these small feeder roots. (Encyclopedia Britannica Online http://www.britannica.com/eb/article-9054526/mycorrhiza)
Amanda M
Enhacement: Liz Foster

Note the small white feeder roots. http://pubs.caes.uga.edu/.../B813-w.htg/B813-7b.jpg, (University of Georgia) Feeder Roots (enhancment): Feeder roots are responsible for the majority of absorbtion of nutrient of a tree. even though feeder roots are only 1/6 inches in diameter, they make up a large portion of a trees root system surface area. These smaller roots grow outward and predominantly upward from the large roots near the soil surface, where minerals, water and oxygen are relatively abundant. Under normal conditions the feeder roots die and are replaced on a regular basis. (http://www.ext.colostate.edu/pubs/garden/02926.html) - VanessaV

Fibrous Root System: Root system in plants which no one root is more prominent than the others. Typically shallower than tap root system and the tenacity with which they cling to soil particle make such plants especially well suited as ground cover for the prevention of soil erosion. (Biology of Plants, 7th edition, Peter H. Raven, pg. 528 – 529)

Fibrous root system of a hydroponically grown plant.
http://commons.wikimedia.org/wiki/Image:Roots.JPG
Kevin Christie
Enhancement:
A fibrous root system (sometimes also called adventitious root system) is the opposite of a taproot system. It is usually formed by thin, moderately branching roots growing from the stem. A fibrous root system is universal in monocotyledonous plants and ferns, and is also common in dicotyledonous plants. Most trees begin life with a taproot, but after one to a few years change to a wide-spreading fibrous root system with mainly horizontal surface roots and only a few vertical, deep anchoring roots. Weeds have fibrous root systems, and that is why some are so hard to pull from the ground. Also, if extra roots remain in the soil, the weeds may grow back again.
http://en.wikipedia.org/wiki/Fibrous_root_system
Krista Neufeld Enhancement: Grasses and other monocotyledons have a fibrous root system, characterized by a mass of roots of about equal diameter. This network of roots does not arise as branches of the primary root but consists of many branching roots that emerge from the base of the stem.(Britannica On-line)Amanda Last

Germination - This is the process whereby growth emerges from a period of dormancy. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. Germination is the first stage of the making of the seedling. The seed of a higher plant is a small package produced in a flower or cone containing an embryo and stored food reserves. Under favorable conditions, the seed begins to germinate, and the embryonic tissues resume growth, developing towards a seedling. Below is an image of a sunflower seedling just 3 days after being planted. (http://en.wikipedia.org/wiki/Image:Sunflower_seedlings.jpg
(http://en.wikipedia.org/wiki/Germination)

Krista Neufeld

Germination Enhancement: The three most important factors that germination is dependent on are water, oxygen, and temperature. Some seeds require exposure of light. Germination is not possible until the seed imbibes enough water, the surrounding soil contains enough oxygen for aerobic pathway, and the specific temperature range for the particular species is met. (Biology of Plants, Raven, p 504) Kirsten Jorgensen
Ground Meristems - Nicole L. The primary meristem, or meristematic tissue, that gives rise to the ground tissue. (biology of Plants, 7th edition, pg G-10) The primary meristem in vascular plants that gives rise to the nonvascular tissues, such as cortex, pericycle, and pith. Within the seeds of angiosperms, it surrounds the procambium. The primary meristem that differentiates into the pith and cortex (http://dictionary.reference.com/browse/Ground Meristem)
Enchanement: Nick N
Below is a diagram of the root apical meristem, the ground meristem is located around the outside of the procambium.

www.answers.com/topic/apical-meristem

Imbibition: Derived from the Latin word “imbibere” which means “to drink”, imbibition refers to the movement of water into a seed. This absorption of water into the colloidal material of cells in a seed causes swelling and increases Turgor pressure. Imbibition is critical in seed germination because without the subsequent swelling the embryo would not be able to escape the seed coat. The excessive presence of water also initiates the physiological changes that lead to germination.

(Biology of Plants, 7th Edition, Peter H. Raven, pg 76, G-12) (Koning, Ross E. "Home Page for Ross Koning". Plant Physiology Information Website. 1994. http://plantphys.info/seedg/seed3.html) Picture from: http://plantphys.info/seedg/seed3.html– Tori Waites

Meristematic Region-Danielle Dornik-(merizein- to divide)- Embryonic tissue regions, primarily concerned with formation of new cells. The meristematic region consists of meristematic tissue:

Root Cap
Promeristem
Root apical meristem(protoderm, ground meristem, procambium)
Primary meristems

The meristematic region is prtected by the root cap. The cells are very active and divide rapidly to form new cells which differentiate later to form more specialized root tissue. The cells of this region also replace the cells rubbed off from the root cap and provide additional cells for the next region.
(Biology of Plants, Peter H Raven G-14)
(http://www.botany.uwc.ac.za/sci_ed/grade10/anatomy/roots.htm) Enhancement (Stephanie Lauer): this is a cross section of a root and a shoot which shows the different meristematic tissues, where they are located and what makes them up. http://cache.eb.com/eb/image?id=5599&rendTypeId=4

Mucigel: Mucigel is a slimy sheath covering the surface of roots (Raven G-14). It is part of the rootcap that penetrates through the soil. As most soil is compact and coarse, mucigel acts as a lubricant to aid the root in pushing through the soil. It accumulates in the golgi vesicles and is secreted through the root cap cells (Raven pg. 530). Due to its sticky nature, soil will bind and this benefits the root through water and nutrient absorption. It also encourages the growth of fungi and bacteria that are able to correct nitrogen in the soil. http://dictionary.reference.com/browse/mucigel --John

Enhancement (Nicole L) Image from http://www.vitalearth.com/images/news/rizo-root.gif Image shows the mucigel around the outside surface of the root

Enhancement: Some functions of Mucigel are: Nutrient absorption-Carboxyl groups in mucigel influence ion uptake, and organic acids in mucigel make certain ions more available to plants. Also, fatty acids, lectins, and sterols in mucigel may help establish beneficial symbioses with soil microbes. Protection-It protects roots from desiccation and contains compounds that diffuse into the soil and inhibit growth in other roots. (Plant Physiology, www.cartage.org.lb/en/themes/sciences/botanicalsciences/PlantsStructure/Roots/Roots.htm) Mark Haywood-Farmer

Mycorrhizae- Myco-fungus rhiza-root -A symbiotic association between certain fungi and plant roots; characteristics of most vascular plants. (Biology Of Plants, Peter H. Raven,p262)
3 types:
Ectomycorrhizae-fungus forms sheath around root. Penetrates between cells of cortex to facilitate nutrient exchange
ectomycorrhizas of Suillus subluteus with Pinus resinosa (the branched ends of the short lateral roots)

Endomycorrhizae- vascular arbuscular mycorrhizae (VAM) Penetrates the corticle cells, doesn’t penetrate cell membrane of form sheath around root. More common than ectomycorrhizae.
colonization of a root by an endomycorrhizal fungus. Note hyphae, arbuscules and vesicles. (see Fig 21 in Brundrett et al. 1985 Can. J. Bot 63: 184)

Orchid Mycorrhizae-special type. a symbiotic relationship between the roots of plants of the family Orchidaceae and a variety of fungi
root cells of Goodyera oblongifolia containing coils (pelotons) of hyphae (probably of a mycorrhizal Rhizoctonia).

Thomas J. Volk, University of Wisconsin-La Crosse (http://www.uwlax.edu/BIOLOGY/VOLK/FUNGI3/index.htm)
all pictures and descriptions from http://www.mycolog.com/chapter17.htm
-Danielle Dornik

Enhancement: (Nikki Heim)

About 95% of the world’s land plants form the mycorrhizal relationship in their native habitats. It is estimated that mycorrhizal fungal filaments can make up hundreds to thousands more soil volume compared to roots alone. Mycorrhizal fungus benefit plants by improving nutrient and water uptake for plant growth, root growth, resistance to disease, and reduced drought stress.

References: Mycorrhizal Application, Inc. Online. Access at http://www.mycorrhiza.com/index)

Mycorrhizae Enhancement 2: To emphasize that the relationship is mutualistic, the plant provides the fungi with energy. (The Ecology of Mycorrhizae, Allan, p.1) kirsten jorgensen

Nitrogen fixation (Russ Fountain)
The process by which nitrogen in the atmosphere is converted into nitrogenous compounds by the action of micro-organisms.(“nitrogen fixation” The Free Dictionary. http://encyclopedia.farlex.com/nitrogen+fixation) Symbiotic nitrogen fixation occurs in plants that harbor nitrogen-fixing bacteria within their tissues. The best-studied example is the association between legumes and bacteria in the genus Rhizobium. Each of these is able to survive independently (soil nitrates must then be available to the legume), but life together is clearly beneficial to both. Only together can nitrogen fixation take place. (Symbiotic Nitrogen Fixation - http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/N/NitrogenFixation.html)
Enhancement (Sarah Slater): Nitrogen is one of the most abundant elements in the earth’s atmosphere and is an essential part of plant growth. When land is used for agriculture the soil is drained of nitrogen, thus farmers rotate crops with nitrogen fixing plants. Examples of plants commonly used for nitrogen fixation are legumes, which include alfalfa. Alnus Rubra is an example of a tree that also fixes nitrogen. In the picture below you can see the root nodules, which is where the nitrogen fixation takes place.
Picture found at: Reed College <http://academic.reed.edu/biology/Nitrogen/Nfix1.html>

Biology of Plants. Raven. G-14
American Chemical Society http://pubs.acs.org/subscribe/journals/esthag-w/2007/june/science/rr_nitrate.html

Periclinal Wall: Periclinal wall is literally translated as a wall that is parallel to the surface (Raven G-17). It is the exterior wall of epidermal cells. It is also known as anticlinal wall. http://jcs.biologists.org/cgi/reprint/48/1/193.pdf --John

Pericycle: A thin layer of parenchymatous or sclerenchymatous cells that surrounds the stele in most vascular plants. (Merriam-Webster Online, http://www.m-w.com/dictionary/pericycle).
It is plant tissue characteristic of roots: the outer layer of plant tissue surrounding the inner core of the roots and stems of plants stele that conducts moisture and nutrients around the plant
(MSN Encarta Encyclopedia,http://encarta.msn.com/encnet/refpages/search.aspx?q=Pericycle ). Lee Williams
Primary phloem (Dennis Murengi) – This is defined as the phloem of the primary plant body. (arabidopsis.info) http://arabidopsis.info/cgibin/ontology/nasc_po/go.cgi?action=query&query=phloem&search_constraint=terms&view=query Primary phloem, are formed by the apical meristems of root and shoot tips; it may be either protophloem, the cells of which are matured before elongation (during growth) of the area in which it lies, or metaphloem, the cells of which mature after elongation. Sieve tubes of protophloem are unable to stretch with the elongating tissues and are torn and destroyed as the plant ages. (www.britannica.com)
http://www.britannica.com/eb/article-9059738/phloem
Procambium- A primary meristematic tissue that gives rise to primary vascular tissues (Raven, Biology of Plants, Pg. 498). The part of the meristem of a plant that forms cambium and primary vascular tissue (Britannica Online Encyclopedia).
As the long band of red procambium continues to divide, some of their progeny cells will become vascular tissue-- xylem and phloem (Plant Anatomy Laboratory, James D. Mauseth, University of Texas). Tessa J

Promeristem: The initiating cells in the apical meristem (Biology of Plants, Peter H. Raven, pg.531) . These are the cells that are closest to the root tip and are responsible for producing the cells for the rest of the meristem (http://www.sbs.utexas.edu/mauseth/weblab/webchap6apmer/6.2-2.htm).

-Morgan Traverse

Enhancement (Daniel Struthers): Promeristems are continually in the process of dividing cells and are present for the entire life of the root. When the root cap wears away due to root movement through the soil it is continuously being built back by the cells created from the promeristem. Source: The American Journal of Botany (online). http://www.jstor.org/view/00029122/di001736/00p0049a/0

Protoderm: Formed by periclinal divisions, the protoderm is the precursor of the epidermis. It is the primary meristematic tissue that develops into dermal tissue.(Biology of Plants, Raven, p 498), (Plant Anatomy, 4th Ed., Fahn, p 539)

http://www.northern.edu/ramsayj/etechWeb/images/roots/zea_rtls1B_copy.JPG. Retrieved November 26, 2007.text and photo-Kirsten jorgensen Enhancement: (Liz Foster) The protoderm is the outermost layer of cells across the apical meristem and the leaf primordium. The light mauvey purple is the protoderm. www.sbs.utexas.edu/mauseth/weblab/webchap6apmer/6.2-2.htm (University of Texas)

Protophloem (Kristie Seaborn) the first-formed elements of the primary phloem, the cells of which mature before the elongation of the surrounding plant tissue; metaphloem (Oxford English Dictionary). The protophloem mother cell (PMC) undergoes two successive asymmetrical divisions: the first one gives rise to a smaller cell that will differentiate into a companion cell, and a larger one that divides again asymmetrically yielding another companion cell and a protophloem sieve element (http://jcs.biologists.org/cgi/content/abstract/75/1/165).
Enhancement: By Conyr Aird image 1

Image 2
These two images are photos of early vascular cell development and clearly depicts from left to right within the trace protoxylem, procambium, and protophloem in the first picture and are labeled in the second. ( Image 1 retrieved from The Stems webpage at the addresshttp://images.google.ca/imgres?imgurl=http://sols.unlv.edu/Schulte/Anatomy/Stems/PineVascClose.jpg&imgrefurl=http://sols.unlv.edu/Schulte/Anatomy/Stems/Stems.html&h=819&w=1024&sz=353&hl=en&start=9&um=1&tbnid=gzi0YovZ19BqUM:&tbnh=120&tbnw=150&prev=/images%3Fq%3Dprotophloem%26svnum%3D10%26um%3D1%26hl%3Den image 2 retrieved from botany Hawaii at the addresshttp://images.google.ca/imgres?imgurl=http://www.botany.hawaii.edu/faculty/webb/BOT410/Phloem/ProcambiumLSLab.jpg&imgrefurl=http://www.botany.hawaii.edu/faculty/webb/BOT410/Phloem/Phloem-1.htm&h=344&w=300&sz=34&hl=en&start=6&um=1&tbnid=LLe_nBJLvUw9LM:&tbnh=120&tbnw=105&prev=/images%3Fq%3Dprotophloem%26svnum%3D10%26um%3D1%26hl%3Den)

Protoxylem (Stephanie Lauer)– “proto” meaning first but not fully functional. The part of the primary xylem that consists of tracheids (Ross E. Koning 1994) which develops first and matures during elongation of roots, stems and leaves of the plant that it is found in (Raven, Biology of Plants, pg 517) . Koning, Ross E. 1994. "Root Vocabulary". Plant Physiology Website. http://plantphys.info/Plant_Biology/rootvocab.html (November 28, 2007)
Enhancement: (Dennis Murengi)-The image below shows a cross section of a root’s region of elongation. The location of the protoxylem is clearly indicated. (www.puc.edu)
http://www.puc.edu/Faculty/Gilbert_Muth/phot0039.jpg

Radicle: The embryonic root enclosed within a seed. (Raven, G-20) The radicle is attached to the hypocotyl inside the seed, and is the first organ to emerge from the germinating seed. (Campbell Reece, 7th Edition, pg 780)
Amanda M

Enhancement: The radical is made up of the root apical meristem and the root cap. It is located at the lower end of the hypocotyl. During seed germination, the radical is the first to emerge from the seed and it plants itself into the soil. (Biology of Plants, 7th edition, Peter H. Raven Pg. 507).
Ilustration of radical emerging from seed

Enhancement by Daniel Struthers(text and picture)

Root Nodules: Enlargements or swellings on the roots of legumes and certain other plants inhabited by symbiotic nitrogen-fixing bacteria. The root nodules of legumes consist of a relatively narrow cortex, which surrounds a large central zone containing both bacteroid-infected and uninfected cells. Vascular bundles, which radiate from the point of attachment of the nodule to the root, occur in the inner cortex. (Biology of Plants, 7th edition, Peter H. Raven, pg. 657-658)

Nitrogen-fixing nodules on the roots of a legume.
http://www.bio.usyd.edu.au/DavidDay/root_nodules.jpg
Kevin Christie
Enhancement: Root nodules are usually host to the Rhizobium and Bradyrhizobium bacterias, which are extremely effective nitrogen fixers. There is a symbiotic relationship between these nitrogen fixing bacterias and the plants that they inhabit. The bacteria provides the plant with a form of nitrogen that it can use to make protein, while the plant in turn provides the bacteria with an energy source.
Amanda M

Taproot system:Taproot system derives directly from the first root that emerges from a seed that is called the radicle. It forms a central root, the taproot, which grows vertically down into the soil. (http://www.botany.uwc.ac.za/sci_ed/grade10/anatomy/roots.htm) The taproot is larger in diameter with a limited amount of smaller branches extending laterally referred to as the lateral roots. Taproots generally grow deep into the soil to obtain nutrients and water. It functions for storage and transport, providing reserves of food in the form of a carbohydrate or for reaching water deep in the ground. (Taproot – Botany) Examples of taproot system plants are nut trees, carrots, radishes, parsnips and dandelions. (Master Gardener. Ohio State University Extension)
References: http://www.botany.uwc.ac.za/sci_ed/grade10/anatomy/roots.htm (Taproot – Botany) http://www.cactus-art.biz/note-book/Dictionary/Dictionary_T/dictionary_tap_root.htm
(Master Gardener. Ohio State University Extension) http://www.hcs.ohio-state.edu/mg/manual/botany.htm
-Nikki Heim
Enhancement
Most trees begin life with a taproot, but after one to a few years change to a wide-spreading fibrous root system with mainly horizontal surface roots and only a few vertical, deep anchoring roots. The taproot is larger in diameter than the lateral roots. Lateral roots, which originate from the pericycle, branch off from the taproot, and subsequent lateral roots can branch off other lateral roots. A typical mature tree 30-50 m tall has a root system that extends horizontally in all directions as far as the tree is tall or more, but well over 95% of the roots are in the top 50 cm depth of soil. http://www-plb.ucdavis.edu/labs/rost/Tomato/Roots/taproot.html
Mike Tomlinson
Enhancement- This picture shows the visual difference in a tap root (carrot) vs. the fibrous root which is an onion. www.botony.hawaii.edu Jess.E.W

Turgor Pressure: From the Latin word “turgor”, meaning “a swelling”; Turgor pressure refers to the hydrostatic pressure in a plant cell that results from osmosis/imbibition. As the water flows into the cell it swells and the water pushes against the cell wall. The pressure of the water against the cell wall is Turgor Pressure. The swelling of the cells due to increased Turgor pressure causes the embryo inside a seed to enlarge and eventually split the seed coat, allowing germination. (Biology of Plants, 7th Edition, Peter H. Raven, pg 75, G-25) (Biology, 6th Edition, Neil A. Campbell, pg 752, Glossary) –Tori Waites
Enhancement:
It is determined how much water is in the vacuole and resulting from osmotic pressure. Turgid plant cells contain more water than flaccid cells and exert a greater osmotic pressure on its cell walls. The pressure of each cell wall against surrounding cell results in stiffness that allows the plant to stay upright.

Ref:
http://www.ccr.buffalo.edu/etomica/app/modules/sites/Osmosis/Background1.html
Campbell, N. A., Reece, J. B. Biology: Sixth Edition; Benjamin Cummings: New York, NY, 2002; Vol. 1.
-Scott Horley

Compare & Contrast (first word alphabetical)
Adventitious roots/Feeder roots: Amanda Last
Adventitious root (syn. stem root)A root that arises from a stem, rather than from the primary root. http://glossary.gardenweb.com/glossary/adventitious_root.html Referring to a structure arising from an unusual place, such as buds at other places than leaf axils, or roots growing from stems or leaves. (Biology of Plants, Raven, G-1)
Some roots, called adventitious roots, arise from an organ other than the root—usually a stem, sometimes a leaf. They are especially numerous on underground stems. The formation of adventitious roots makes it possible to vegetatively propagate many plants from stem or leaf cuttings. (Britannica On-line encyclopedia).
Feeder Roots: Fine roots actively engaged in the uptake of water and minerals. The bulk of most feeder roots usually occurs in the uppermost meter of soil. In most trees feeder roots primarily occur in the upper 15cm of soil, which is normally richest in organic matter (Biology of Plants, Raven, p.529) The feeder, or fine, roots are similar to those of herbaceous vascular plants until, as they mature, they begin to undergo secondary growth(Britannica On-line Encyclopedia) Both the adventitious roots and feeder roots are part of the root system. Adventitious roots come do not come from the primary root but rather from a stem or bud. Feeder roots are finer and take part in absorbtion of water and minerals.

Enhancement(Adventitious roots/Feeder roots) Russ Fountain
(Above Left)This is an example of a monocot with adventitious roots.The roots are coming off stems in this instance, and are therefore called adventitious. (“Monocot or Dicot – Adventitious Roots” - http://www.bridgewater.edu/~lhill/adventitiousroots.htm)
(Above Right)At the surface, feeder roots mix with lawn and shrub roots and compete for the water, oxygen and minerals that are more abundant near the surface. (“Tree Root Basics” Southern Nevada Water Authority - http://www.snwa.com/html/land_trees_roots.html)
Adventitious roots/Fibrous root system (Dennis Murengi) Adventitious roots: These are roots growing from stems or leaves. (Biology of Plants 7th Edition G-1) Fibrous root system: A root system made up of many threadlike members of more or less equal length. (www.thefreedictionary.com) http://www.thefreedictionary.com/fibrous+root Adventitious roots and fibrous roots are similar in the functions they perform. These functions include anchorage, storage, absorption, and conduction/transport. However, adventitious roots and fibrous root system differ in terms of how they from. Adventitious roots arise from the stems or leaves of plants. On the other hand the fibrous root system develops from adventitious roots arising form the plant’s stem. (www.thefreedictionary.com) http://www.thefreedictionary.com/fibrous+root

The image on the left shows adventitious roots growing from a leaf, while the image on the right shows a fibrous root system.

Apical meristem/lateral meristem Apical meristem:
Tissue located at the tip of stems and roots where cells are continuously and repeatedly dividing. Cell division of apical meristems results in primary growth, increasing the length of stems and roots. (Raven, 7th ed.) (Biolog online: http://www.biology-online.org/3/7_meristems.htm)
Lateral meristem

Tissue located in the vascular cambium and cork cambium of stems and roots that are no longer elongating. Cell division in these tissues produces secondary growth, increasing the thickness of the plant body. (Raven, 7th ed.) (Biolog online: http://www.biology-online.org/3/7_meristems.htm)

Apical and lateral meristems are both tissues where cell division contributes to new growth in the plant body. Lateral meristems increase the diameter of stems and roots while apical meristems increase the length.
Katherine Loewen

This is an image of the apical meristem. www.answers.com (Matti Harper)

This is an image comparing the apical and lateral meristems.
www.agen.ufl.edu/.../lect/lect_15/22_2AT.GIF (Matti Harper)

Apical meristems/ Primary meristem The apical meristem is the growing tips of a root that is undifferentiated meristematic tissue. This is were new growth begins with new cells forming at the tips of the roots and shoots. From the primary meristem arise from the apical meristems that differentiate into three kinds of primary meristems including the protoderm, procambium, and ground meristem. Ref: http://arnica.csustan.edu/boty1050/Tissues/tissues.htm Scofield and Murray (2006). The evolving concept of the meristem. Plant Molecular Biology 60:v–vii -Scott Horley

Apical Meristem: Embryonic plant tissue in the tips of roots and the buds of shoots that supplies cells for the plant growth in length (Biology 7th Edition, Campbell and Reece, pg. 414) It is a mass of undifferentiated cells at the tip of the stem and is responsible for primary growth (http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/F/Flowering.html).
Ground Meristem: The primary meristem, or meristematic tissue that gives rise to the ground tissues (Biology of Plants, Raven, pg. 498). It develops into the pith and the cortex and surrounds the procambium, which will extend into other regions of the embryo as embryogenesis continues (http://dictionary.reference.com/browse/ground%20meristem).
Summary: The apical meristem and ground meristem are similar in that they are both responsible for primary growth and are both parts of the meristematic regions of a plant. They differ in that apical meristems are part of the vascular tissue system and the ground meristem is part of the ground tissue system. They are also different in that the apical meristem is responsible for plant growth in length where the ground meristem develops into the pith and cortex.

(Lacey Loewen)

Casparian Strip and Exodermis-Danielle Dornik

Casparian Srip	Exodermis
• Band of Primary cell walls • Contain suberin(fatty substance) • Stop water and minerals going though side walls • Is in Endodermal cells and Exodermal cells(Exodermal only in angiosperms) • Functions mainly in root hair zone-where water is taken up	• Outer layer of cortex • Band of Casparian strip (Agiosperms only!!) • Have radial and transverse walls • Located below epidermis • Reduces water loss for the root • Provides defence against microorganisms

As shown above one can link the casparian strip functions to that of the Exodermis. It is important to remember that water can not go through the side walls. Also that the exodermis is only in agiosperms!
Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-9
http://www.eeob.iastate.edu/classes/bio454/docs/404root104.pdf

Endodermis/Exodermis
The exodermis is the outermost layer of the cortex, whereas the endodermis is the innermost layer of the cortex. Both cells are characterized by Casparian strip within radial and transverse wall. They both direct water through the protoplasts, where the exodermis reduces water loss and the endodermis filters the water reducing the risk if disease entering the stele. The endodermis is a single layer of cells and the exodermis is one or more cells in depth. (Biology of Plants 6th Edition)-Derek Burdikin

Sexual reproduction/ Asexual reproduction in plantsThe vast majority of plants reproduce sexually. This can be only means of reproduction or it can be in combination with one or more means of asexual reproduction. Sexual reproduction requires haploid spores from a second parent for fertilization.Asexual reproduction involves only one parent that produces genetically identical offspring. It is also known as vegetation reproduction because the clones are usually fragments of the parent plant. Examples of asexual reproduction are fragmentation and layering.Each method offers advantages in certain situations. Asexual means is best suited for stable, favoring environments where the clones will be as productive as the parent. If the conditions are changing or the parent plant is not best suited for the environment than sexual reproduction is beneficial. Kirsten (Biology 7th ed., Campbell & Reece, p. 781), (Biology of Plants, Raven, p 158)

Tap Root System/Fibrous Root System (Kevin Christie) Tap Root System: The primary root of a plant formed in direct continuation with the root tip or radicle of the embryo: forms a stout, tapering main root from which arise smaller, lateral roots. The older lateral roots are found nearer the base of the root (where the root and stem meet), and the younger ones nearer the root tip. Taproot systems generally penetrate deeper into the soil than fibrous root systems.( (Biology of Plants, 7th edition, Peter H. Raven, pg. 528 – 530) Fibrous root system: Root system in plants which no one root is more prominent than the others. Typically shallower than tap root system and the tenacity with which they cling to soil particle make such plants especially well suited as ground cover for the prevention of soil erosion. (Biology of Plants, 7th edition, Peter H. Raven, pg. 528 – 529)

Transverse Wall/Radial Wall (Caitlin Deas)
Both a transverse wall and a radial wall are anticlinal walls in the root endodermis. They are perpendicular to the root (Botany, http://biology.jbpub.com/Botany/interactive_glossary_showterm.cfm?term=anticlinal%20wall). The transverse wall is at a right angle to the long axis of the root along the top of the cell, while the radial wall is at a right angle to the root’s long axis but on the side of the cell.
(University of Minnesota Extension) http://www.extension.umn.edu/distribution/naturalresources/components/6413ch1.html
Lignin and suberin impregnate the transverse and radial walls to form the Casparian strip, making these walls important for blocking water from entering the cells without being filtered.
(The Ecotree)
http://www.bcb.uwc.ac.za/ecotree/root/rootA.htm
Below is an image of the transverse and radial walls showing the Casparian strip. The long axis of the root would be in the front of the picture, blocking the view of the cells.

(The Ecotree)
http://www.bcb.uwc.ac.za/ecotree/root/images/Endodermis.GIF

Vascular Cambium / Stele: Vascular Cambium – cylindrical sheath of meristematic tissue, the division of which produces secondary xylem and phloem (Raven, Biology of Plants, pg G-25). Stele – central cylinder, inside the cortex of the roots and stems in vascular plants (Raven, Biology of Plants, pg G-22), the vascular tissue inside the stem or roots (Campbell & Reece, Biology 7th ed. Glossary). Primary vascular tissues (primary xylem and phloem), and in some vascular plants the pith, make up the central cylinder, or stele, of the stem and/or root in the primary plant body (Raven, Biology of Plants, pg 371). Secondary growth of the xylem and phloem into the secondary xylem and phloem is caused by the activity of the lateral meristem called the vascular cambium which adds layers of vascular tissue (secondary xylem and phloem) (Campbell & Reece, Biology 7th ed. Pg 720). Stephanie Lauer
Enhancement: (AarenS) Vascular cambium can be seen in picture below, note the location between the sapwood and secondary phloem.

(www.britannica.com)
Stele shown below, comprised of phloem, cambium, xylem and pericycle.

www.apsnet.org
Vascular Cylinder/Pericycle (Daniel Struthers): Both part of the vascular tissue system and originate from the procambium and found in the root system. They are both important parts of the stele. The Vascular Cylinder of the root system consists of primary vascular tissues and one or more layers of nonvascular cells. Consisting of the xylem and phloem, it is responsible for water and food transportation. The Pericycle completely surrounds the vascular tissues within the vascular cylinder. In most seed plants, lateral roots arise in the pericycle and also contributes to secondary growth in the vascular cambium.(Biology of Plants, 7th Edition, Peter H. Raven, Pg. 538)

Illustration of Vascular cylinder/pericycle (www-plb.ucdavis.edu/.../Roots/rootorg.html)

The Seed: Structure, Dispersal, and Dormancy

DennisMurengi — Thu, 29 Nov 2007 17:30:18 CST

Afterripening (Dennis Murengi)
Apical meristems- Liz Foster
Aril
Catkin
Chilling requirement
Cladoptosis - Nick Niddrie
Cone crop monitoring-Danielle Dornik
Cotyledons - Amanda Miller
Dark-imposed dormancy - Nicole L
Dicotyledon
Dormancy - Kirsten Jorgensen
Double dormancy
Embryo - Andrea Chapman
Embryo dormancy
Embryo immaturity
Endosperm
Epicotyl
Follicle
Growth regulators- Liz Foster
Hypocotyl - Amanda Last
Megagametophyte - Sarah Slater
Monocotyledon Jessi.E.W
Nucellus
Pericarp
Plumule
Polycotyledon
Primary seed dispersal
Quiescence
Radicle
Scarification - Morgan Traverse
Secondary seed dispersal- Nicole L
Seed coat - Russ Fountain
Seed coat dormancy- Kristie S
Seed coat impermeability - Stephanie Lauer
Serotinous - Nick Niddrie
Stratification - Sarah Slater
Strobilus - Krista Neufeld
Suspensor- Amanda Last
Wing loading

Definitions (in alphabetical order)
After-ripening (Dennis Murengi) – This refers to the metabolic changes that must occur in some dormant seeds before germination can occur. (Biology of Plants 7th Edition, G-1) The length of after-ripening period in different species may vary from a few weeks to many months. After-ripening helps seeds germinate at a time when conditions are most favourable for growth. (encyclopedia.farlex.com)
http://encyclopedia.farlex.com/after-ripening
Enhancement:(Kevin Christie)

Apical Meristem: The apical meristem is the area of a plant where the cell division occurs. The apical meristems are located at the tip of all roots and shoots as this is where most of the cell division takes place. They are the cause of tip growth. The cells of the meristem have potentially unlimited ability to divide, but this is controlled by the plant. The apical meristem produces the three primary meristems, the procambium, ground meristem and the protoderm plus the root cap. A diagram of the two types of apical meristems. Shoot apical meristem on the left and root apical meristem on the right. Liz Foster
http://cache.eb.com/eb/image?id=5599&rendTypeId=4, www.biologie.uni-hamburg.de/b-online/e04/04c.htm (University of Hamburg), http://www.botany.hawaii.edu/faculty/Webb/BOT410/Roots/ApicalMeristems.htm (University of Hawaii)

Aril: (Nikki Heim) A seed covering formed by an outgrowth at the base of the ovule. This seed covering can be brightly colored and fleshy, which may aid in dispersal by attracting animals that eat it, and in the process, carry the seed away from the parent plant. (Biology of Plants) The animal will eat the aril, and without the digestion of the seed, the animal will excrete the seed, allowing for dispersal. Arils are found in woody plants as the yews and nutmeg and in members of the arrowroot family, the genus Oxalis, and the castor bean. (Encyclopedia Britannica) References:
Biology of Plants. 7th ed. Peter H. Raven. Pg. G3
(Encyclopedia Britannica) http://www.britannica.com/eb/article-9009426/aril

The aril of a Western Yew
Image found @ www.daveingram.ca/.../Media/yew_aril.jpg

Enhancement: The true arillus is an accessory seed-covering, more or less incomplete, formed between the time of fertilization and the ripening of the seed, by a growth from the apex of the funiculus, at or just below the hilum.(Oxford English Dictionary) A fleshy appendage growing at or about the hilum of a seed. http://glossary.gardenweb.com/glossary/aril.html Amanda Last

Catkin: is a spike like inflorescence( cluster) of unisexual flowers that is found only in woody plants (biology of plants glossary G-4) Also called and Ament, found in willows, birches and oaks, is a dense drooping, cylindrical, cluster.(http://www.thefreedictionary.com/catkin)- Vanessa V
http://images.jupiterimages.com/common/detail/72/63/22576372.jpg
Enhancement: Elongated cluster of single-sex flowers bearing scaly bract and usually lacking petals.Wind carries pollen from male to female catkins or from male catkins to female flowers that take a different form (e.g., in spikes) (Encyclopedia Britannica online). Tamiki N Enhancement: They can be found in many plant families, including Betulaceae, Fagaceae, Moraceae, and Salicaceae. (World book Encyclopedia) Travis Unsworth

Cladoptosis: Coming from the Greek words Clados = branch, ptosis = falling. (UBC Botanical Garden and centre for plant research http://www.ubcbotanicalgarden.org/education/cladoptosis.php) It is the shedding of branches, because they are brittle, it can act as a method of asexual reproduction, when the branches drop they can root. Cladoptosis can also act as a response to drought or disease. (K. V. Bhat, T. Surendran, K. Swarupanandan (1986). "Anatomy of Branch Abscission in Lagerstroemia microcarpa Wight". New Phytologist 103) Nick N
Enhancement (Sarah Slater): Cladoptosis most often occurs in the dry and warm summer temperatures. It can also occur when trees are growing in poor locations where their needs are poorly met. Branches are often dropped if part of a shade tree is growing in a very sunny area or part of a tree that needs sun in growing in a shady area. Cladoptosis is a trees response to stress. If a tree is having a hard time keeping certain branches alive, it is more beneficial to drop them then to use energy to keep them alive. Sometimes when the branches fall on the ground they are able to root, if the right growing conditions are met. Knots in trees are formed by cladoptosis. Hole’s Publications <http://www.enjoygardening.com/?p=24>
Scripps Networks < http://www.hgtv.com/hgtv/gl_gardening_basics/article/0,,hgtv_3589_3053813,00.html>
University of British Columbia < http://www.ubcbotanicalgarden.org/education/cladoptosis.php>

Cotyledons - The first leaves of the plant, enclosed inside the seed, the "seed leaves" (Raven, pg. 500) part of the sporophyte generation of the plant, broken into categories such as dicots, monocots, etc. depending on the number of seed leaves present. (Campbell Reece 7th Edition, pg.600)
Amanda M Enhancement:(Mallory Hazell) - A leaf of the embryo of a seed-bearing plant. Most cotyledons emerge, enlarge, and become green after the seed has germinated. Cotyledons either store food for the growing embryo (as in monocotyledons) or absorb food that has been stored in the endosperm (as in other angiosperms) for eventual distribution to the growing parts of the embryo. Also called seed leaf. The number of cotyledons present in an embryo is an important character in the classification of flowering plants (angiosperms). Monocotyledons (such as grasses, palms, and lilies) have a single cotyledon, whereas dicotyledons (the majority of plant species) have two. In seeds that also contain endosperm (nutritive tissue), the cotyledons are thin, but where they are the primary food-storing tissue, as in peas and beans, they may be quite large. After germination the cotyledons either remain below ground (hypogeal) or, more commonly, spread out above soil level (epigeal) and become the first green leaves. In gymnosperms there may be up to a dozen cotyledons within each seed. (http://www.thefreedictionary.com/Cotyledons) (http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0006930.html)
Enhancement: By Conyr A. This image shows the difference in seed shape by giving us a cross section or a monocot and dicot seed. (image retrieved from the webpage Palaeos: The Trace of Life on Earth at the address http://www.palaeos.com/Plants/Lists/Glossary/GlossaryA.html)

This image shows the the cotyledons within a growing dicot seed. (image retrieved from the webpage Biology 252 Plant Morphology and Systematics Fall, 2005 at the addresshttp://www.stolaf.edu/people/ceumb/bio252/Capsella3.jpg)

Dormancy(From the latin word meaning “to sleep”). A condition adopted by seeds to vastly decrease metabolic rate and suspend growth and development until specific growing conditions have been met. This increases the chance that germination will occur at a time and place most advantageous to the seedling. The environmental cues to impose dormancy include cold exposure, and darkness. Dormancy can also be imposed by hormones and serotinous cones. Conditions required to break dormancy vary between plant species. Dormancy can be broken by the increase in temperature and light brought by spring, fire or moisture. Kirsten(Biology 7th ed., Campbell & Reece, p. 779), (Biology of Plants, Raven, p. 505) Enhancement (Stephanie Lauer): the most common causes of dormancy in seeds are the physiological immaturity of the embryo and the impermeability of the seed coat to water and somtimes oxygen. some physiological immature seeds must undergo a complex series of enzymatic and biochemical changes called "after-rippening" before they can germinate. To break the seed coat dormancy the seed must go through external changes such as environmental and physical like the examples listed above. (Raven, Biology of Plants, pg 505)

Double Dormancy- A combination of seed coat (external dormancy) and internal dormancy. To achieve germination with seeds having double dormancy, the seeds must first be scarifies and then stratifies for the appropriate length of time (Overcoming Seeds Dormancy: Trees and Shrubs, Frank A. Blazich, NC State University). Double dormancy combines two or more kinds of dormancy, which is a period of suspended development in a plants lifecycle. In order to promote germination, all blocking conditions must be removed in the proper sequence. This type of dormancy is characteristic of species of trees and shrubs having seeds with hard seed coats (Plant Growth Substances, Richard N. Arteca, Pg. 150). Tessa J

Embryo (Andrea Chapman) – Is a cell that matures from a fertilized egg or zygote and is where organs and tissues begin to form (Raven et al. 2005). The developing tissue and organ systems divide at later stages into the shoot apical meristem and root apical meristem at opposite ends of the embryo. These meristem tissues expand their respective systems through cell division (Steeves and Sussex 1989).

Raven P.H., Evert R.F. and Eichorn S.E. 2005. Biology of plants. Seventh edition. W.H. Freeman and Company. New York, NY. 686 pp
Steeves T.A. and Sussex I.M. 1989. Patterns in plant development. Cambridge University Press. Pg 1 URL http://books.google.ca/books?hl=en&lr=&id=7GCTLqM3FDcC&oi=fnd&pg=PP15&dq=embryo+plant&ots=QFd3x1FTxJ&sig=DgdcdIWeI97rguifhTNeYlS8VcQ#PPA1,M1

Enhancement (Kristie Seaborn) The image below is from seeds that have been opened after the seedcoat was carefully cracked and the seed then softened in water. The almost crystalline red outer layer of the seedcoat (exocarp), roughly 0.5 mm. thick can easily be distinguished from the more leathery, orangish, inner layers. The small pale embryo is attached to two large 'seed leaves' or cotyledons. The cotyledons store food needed for the growth of the emerging seedling. With Texas Mountain Laurel these remain underground as the embryo grows to the light and begins to produce true green leaves to provide nourishment for its continued growth. The embryo also has an embryonic root (radicle) which will develop downwater in order to supply water and nutrients from the soil.

Embryo detached from its two cotyledons.

(https://webspace.utexas.edu/harms/SOSE-HTML/SophoraSeed.html)

Endosperm: (Nikki Heim)
Endo- means within, and sperm means seed, so endosperm means “within the seed”. (Botanical Society of America) The endosperm is the tissue that surrounds and nourishes the embryo in the angiosperm seed. It provides storage of starch, fat, and protein that are used during seed development. (Encyclopedia Britannica) The endosperm can also provide nutrition for the human diet and is commonly found in cereal grains and oilseeds. References:
(Encyclopedia Britannica) http://www.britannica.com/eb/article-9032623/endosperm
(Botanical Society of America) http://www.scientific-conference.net/PlantTalkingPoints/Endosperm.php

Enhancement:

This is a picture of the endosperm displaying the large role that it has.

http://www.public.iastate.edu/~becraft/kernel.jpg

--John

Epicotyl: The stem of an embryo or a seedling thats is located between the cotyledon and the next true leaves.(http://www.thefreedictionary.com/epicotyl) Another description is it is the top part of the axis of a seedling or an embyro. It is above the seed leaves (cotyledons) and below the next leaf or leaves. (Raven G-4) - Vanessa V
http://cache.eb.com/eb/image?id=72144&rendTypeId=35

www.apsnet.org/.../PhotosE-H/epicotyl.htm

epicotyl
portion of the stem of a plant embryo or seedling above the node where the cotyledons are attached

Enhancement: The epicotyl is the embryonic shoot above the cotyledons. In most plants the epicotyl will eventually develop into the stem and the leaves of the plant. In diconts, the hypocotyl is what appears to be the base stem under the spent withered cotyledons, and the shoot just above that is the epicotyl.
In sunflower seedlings, the difference between epicotyl and hypocotyl can be seen from the parts of the stem divided by the first pair of leaves.

Ref: http://www.geo.arizona.edu/palynology/geos581/embryo.gif
-Scott Horley

Follicle-Danielle Dornik (L. folliculus, small ball)- A dry, dehiscent simple fruit derived from a single carpel and opening along one side.
(Biology Of Plants, Peter H. Raven G-9)
‘A kind of fruit, consisting of a single carpel, dehiscing by the ventral suture only (Lindley); formerly used for any kind of capsular fruit.
(Oxford English Dictionary Online)

The single carpel of a follicle splits open along one seam. When completely opened, the carpel resembles a thick, dried leaf. It is easy to see that the single carpel of a follicle is a modified, seed-bearing leaf (megasporophyll).http://waynesword.palomar.edu/termfr1.htm

Growth Regulators: Growth regulators are chemicals produced by the plant that play a very large part in the development of plants. They can be very helpful to plants and there are several brands of commercial growth regulators on the market for gardeners to buy. Growth regulators were first discovered by Charles Darwin and his son in the 1800’s, when they noticed that when grass was covered it would not bend towards the sun. Growth regulators play a role in cell elongation, cell division, cell and organ enlargement, and even dormancy induction. One use that people have is in the clipping of Christmas trees. Every time a shoot is sheared, it stimulates the growth of more because it increases branch density, therefore resulting in a fuller, thicker tree A picture of a Christmas tree that has been sheared to induce the increase branch density. Liz Foster
www.cnr.vt.edu/dendro/forestbiology/htmltext/chapter5.htm, (Virginia Tech) www.umass.edu/umext/floriculture/fact_sheets/greenhouse_management/pgr.html (University of Massachusetts)

Hypocotyl:Amanda Last
1880 C&F. Darwin Movem Pl5 With seedlings, the stem has been called by many botanists the hypocotyledonous stem, but for brevity sake we will speak of it merely as the hypoctyl.Ibid 10 The radicles, hypocotyls, and cotyledons of seedling plants. 1882 Nature23 Mar. 482 Buck-wheat plants grow from small seeds containing a small hypocotyl that enlarges afterwards to an exceedingly long part.(Oxford English Dictionary)
The hypocotyl (embryonic stem) grows several inches above the ground, carrying the cotyledons into the light, in which they become green and often leaflike. (Britannica online)
The portion of an embryo or seedling situated between the cotyledons and the radicle. (Biology of Plants, Raven, G-12).

Picture illustrating the hypoctoyl and cotyledons of a sprouting plant.
Picture from: http://media.allrefer.com/s1/l/h0365200-hypocotyl.jpg
Added by: Amanda Last
Megagametophyte (Sarah Slater): A female gametophyte, developed from a megaspore. In gymnosperms it is located within the ovule of the seed and is food supply and support for the embryo. Megagametophytes are made up of mostly carbohydrates and fats. Biology of Plants. Raven. G-14
Henderson’s Dictionary of Biology. Lawrence, Eleanor. Pg 383
Scarification: Some seeds have such hard seed coats that these coats can only be removed by abrasion. This can includes any mechanical action, like digestion or soaking the seed in acid, that wears away the seed coat enough to allow water or oxygen to enter the seed. (Biology of Plants, Peter H. Raven, pg.637). An example of a tree species seed that germinates this way is Robinia pseudoacacia (black locust). This tree’s seeds germinate after being eaten by birds like the northern bobwhite or small mammals like squirrels (http://www.na.fs.fed.us/spfo/pubs/silvics_manual/Volume_2/robinia/pseudoacacia.htm).

Northern bobwhite. (http://www.birdsasart.com/Bobwhite-group-_H2D1498-Los-Colmenas-Ranch,-Hidalgo-County,-TX.jpg) -Morgan Traverse
Enhancement (Scarification): Seed scarification is a technique used to break dormancy. The seed will not germinate until the seed coat is altered physically. Any process of breaking, scratching, or mechanically altering the seed coat to make it permeable to water and gases is known as scarification (NC State University, “Overcoming Seed Dormancy: Trees and Shrubs”, By Frank A. Blazich and Erv Evens). Artificial scarification, such as abrasion using a knife, file, or sandpaper, is commonly used by horticulturists to promote seed germination (Raven, Biology of Plants, 637). Tessa J

Stratification(Sarah Slater): Artificially meeting the chilling requirement of seeds. Stratification is the action of chilling seeds for an amount of time before exposing them to warm temperatures to break their dormancy. The process involves first soaking the seeds for twenty-four hours, then drying them off to prevent mold growth. The seeds are then put into a cold storage, which is slightly above freezing temperatures for 4-12 weeks depending on the species. Some species require less chill time because they naturally grow within warmer climate than other species. Biology of Plants. Raven. G-22
University of Manitoba < http://www.ncrs.fs.fed.us/fmg/nfmg/glos.html#s>

Stratification(enhancement): Is a proccessed used to overcome internal dormancy regulated by inner seed tissues. The are two types of strtification. Cold stratification is when a seed is chilled. Warm stratification is when a seed is kept at a temperature of 68 to 86 degrees F (for a certain time period) depending on the species.(http://www.ces.ncsu.edu/depts/hort/hil/hil-8704.html) - VanessaV

Secondary Seed Dispersal (Nicole L.) Subsequent movements of that seed by a distinctly different mechanism (ex. wind, water, and animals) Dispersal implies movement—movement away from an existing population (population expansion) or away from the parent organism (population maintenance)
http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=154791 http://en.wikipedia.org/wiki/Biological_dispersal
The pictures are different methods of secondary seed dispersal; bees dispersal of pollen, wind disperses seeds, and seeds getting caught on the fur of animals.

Images from http://en.wikipedia.org/wiki/Biological_dispersal
ENHANCEMENT

Secondary seed dispersal occurs whenever a seed is dispersed in two or more different dispersal events, so that different dispersal agents, mainly birds, contribute to different events. In order for secondary dispersal to occur, primary dispersal must. Any movement of the seed from where it lands from primary dispersal is considered secondary dispersal.

MANUEL NOGALES, DAVID P PADILLA, CONCEPCIÓN NIEVES, JUAN C ILLERA, ANNA TRAVESET (2007)
Secondary seed dispersal systems, frugivorous lizards and predatory birds in insular volcanic badlands
Journal of Ecology 95 (6), 1394–1403.
doi:10.1111/j.1365-2745.2007.01305.x
http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2745.2007.01305.x Enhancement: Animals, Water and Wind are the three main secondary dispersal agents. (http://www.zephyrus.co.uk/seeddispersal1.html ) Travis Unsworth
Seed Coat (Russ Fountain)
The seed coat is the outer protective covering of a seed. Seed coat is a structure of considerable importance, because it forms the barrier between the embryo and its immediate environment. The most important property of the seed coat is its permeability to water and to gas. (Seed Coat Structure of Pinus Koraiensis - http://journals.cambridge.org/download.php?file=%2FMAM%2FMAM11_S02%2FS1431927605503635a.pdf&code=dd0d250f059fc8125e74d9e8bd98cb77) The seed coat develops from the integument of the ovule. It is also called the testa.(“seed coat” The Free Dictionary http://www.thefreedictionary.com/seed+coats)
Seed coat dormancy (Kristie Seaborn) is dormancy imposed on the embryo by the seed coat and other enclosing tissues, such as endosperm, pericarp, or extrafloral organs. The embryos of such seeds will germinate readily in the presence of water and oxygen once the seed coat and other surrounding tissues are either removed or damaged. There are five basic mechanisms of coat-imposed dormancy: Prevention of water uptake, Mechanical constraint, Interference with gas exchange, Retention of inhibitors,and Inhibitor production (http://4e.plantphys.net/article.php?ch=t&id=8). Some seeds of desert species will germinate only when inhibitors in their coats are leached away by rainfall; this adaptation ensures that the seed will germinate only during those rare intervals when desert rainfall provides sufficient water for the seedling to mature (Biology of plants, pg. 505).
Seed Coat Impermeability (Stephanie Lauer)– impermeability relates to the structure of something that cannot be pervaded by liquid (WordReference.com), therefore if a seed coat is impermeable it cannot allow liquid through its outside layer. This relates to the seed coat dormancy in the sense that the seed coat needs to have some external, physical, environmental factor to break the seed coat impermeability so that germination can take place (Raven, Biology of Plants, pg 504) http://www.wordreference.com/definition/impermeability

Strobilus - A strobilus (plural strobili) is an organ of many plants that contains the reproductive structures. Strobili are ordinarily called cones in many of these groups. It isthe cone of a coniferous plant, or a similar cone-shaped structure in some lower plants that consists of closely packed fertile leaves bearing spore-producing organs. Strobili are characterized by a central axis (anatomically a stem) surrounded by spirally arranged structures that bear reproductive parts.

(http://en.wikipedia.org/wiki/Strobilus) (http://uk.encarta.msn.com/dictionary_1861759564/strobilus.html)
Image (http://www.biologie.uni-hamburg.de/b-online/earle/cy/cy/media1.jpg)
Krista Neufeld

Monocotyledon – Angiosperms (flowering plants) are divided in two major groups. Monocotyledons are plants that have only one seed leaf in the embryo. Thus the sprouting seed only has one primary leaf or cotyledon. Monocotyledons have some similar traits that include: flower parts in threes or multiples of three, leaves with parallel veins, fibrous root system predominant, and increase in stem diameter as a result of cell enlargement or the production of cells from the inner cells (rather then from the cambium layer as in dicots). Most monocotyledons are small plants such as grasses, lilies and orchids but palms are also monocotyledons. (Encyclopaedia Britannica and Merriam-Webster) www.visit-islay.com/resources/plants.htm
Enhancement: Many of the world's most important agricultural crops are monocots, such as corn, wheat, barley, and other cereal crops. Monocots have played a huge part in human culture through the ages as a food source, and still do today. For example, corn (a monocot) is the most important crop plant in the United States (Raven, pg. 479) where it is used primarily for animal feed.
Amanda M

Compare and Contrast (first word alphabetical)
Afterripening/Dormancy:
Afterripening is a period of dormancy after a seed is shed during which the synthetic machinery of the seed is prepared for germination and growth. This is because the embryo is not mature enough to germinate. It needs to develop more before this can happen.
Dormancy is a state of quiescence during the development of many plants characterized by their inability to grow, though continuing their morphological and physiological activities. This is so the seed will not germinate too soon. If it did germinate too soon, in the winter for example, the embryo would die. There are many factors or triggers that break this state of dormancy, including afterripening. There are several types of dormancy, which can be imposed by factors such as the embryo hormones (growth regulators), low temperatures (quiescence), embryo immaturity, seed coat impermeability or dormancy and closed cones. These are all broken by different factors.
http://www.healthguidance.org/entry/6425/1/Afterripening-Rest-Period-and-Dormancy.html
http://www.answers.com/topic/afterripening?cat=technology
Krista Neufeld

Aril/Seed Coat: Both an aril and seed coat are vital to the success of reproduction of plants and are grown from the ovule of a seed. As well, they both compose the outer covering of a seed providing support and protection to the inner components. An aril is a fleshy envelope and often brightly colored which can help to attract animals that will eat it and disperse the seed elsewhere (Biology of Plants, Raven G-3). One example of a plant that produces arils is the Pacific Yew. A seed coat on the other hand is much more solid and compact and is not digested by birds or broken down by other methods very easily. It is responsible for seed dormancy by: preventing the expansion of the embryo, keeping oxygen from entering, and preventing the inflow of water (www.britannica.com). Overall, the seed coat is much longer lived and more important to the survival of a seed.
~Quinn
Enhancement: (AarenS) Aril of a yew, attracts birds which eat the fleshy berry like aril, and disperse the seed following digestion.
www.answers.com
Seed coat – protects the enclosed embryo and can be pivotal in ensuring that germination occurs during ideal conditions.
www.urbanext.uiuc.edu

Chilling requirement/Dark-imposed dormancy (Daniel Struthers): Both are results from the Dormancy of the embryo. Phytohormones keep the embryo in dormancy until a certain requirement is met. After this requirement is met then the embryo is ready to germinate. Chilling requirement is one of the types of conditions for some types of species to bring the seed out of dormancy. The seed needs a minimum chilling period to shift hormone balance to growth promotion. This is useful so that the seed doesn’t germinate during winter and expire. Dark-imposed dormancy in a type of growth regulator dormancy of the embryo in which seeds that are buried won’t germinate until they are exposed to light. For example, if a seed is dispersed during winter and is covered by snow it will stay in dormancy until the snow melts and sunlight shines on the seed.
Chilling requirement/Stratification: Dormancy that is imposed by hormones often require low temperatures to germinate. Most wildflowers, like Chrysopsis villosa (hairy golden aster) that seed out in the fall and sit in the soil all winter require this (www.growwildflowers.com). Stratification is the artificial method of achieving this by manually chilling the seeds (Biology of Plants, Peter H. Raven, pg.637)
http://www.swcoloradowildflowers.com/Yellow%20Enlarged%20Photos/2hevi4.jpg -Morgan Traverse
Cladoptosis/Layering
Cladoptosis is derived from the Greek words clados, meaning branch, and ptosis, meaning fall (Jim Hole). It is the annual falling of leafy twigs instead of individual leaves. This process takes amongst most of cypress family (Botany.com). After the branch drops off on the ground, it regenerates into a tree.
Layering occurs naturally for drooping stems whose trailing tips root where they come in contact with the soil. They then send up new shoots from the newly rooted portion of the plant (Encyclopedia Britannica online). Since the new rooted portion and parent plant, the parent plant supplies the food until the new plant has an adequate root system and can survive on its own (Plant propagation.com).

Both cladoptosis and layering produces new roots from branches that are in contact with soils. However, the layering branch is attached to the parent plants, whereas cladoptosis branch is completely separated from the parent plants. Tamiki N
Cotyledon/Dicotyledon The Cotyledon is the trees first leaves or needles. In monocotyledons it absorbs food and in other angiosperms it stores food. (Raven, Biology of Plants 7th edition). Dicotyledons refers to all angiosperms other than monocotyledons. In Dicotyledons they have two cotyledons, and monocotyledons have one cotyledon. (http://www.biology-online.org/dictionary/Cotyledons) –Nick N

Cotyledons/Epicotyl: The cotyledons of a plant are the seed leaves (Campbell Reece, 7th Edition, pg. 601) and the epicotyl is the upper portion of the axis of an embryo seedling, directly above the cotyledons, and below the next leaf. (Raven G-8) The epicotyl is the shoot tip, which usually has a pair of miniature leaves, and it is located above the cotyledons.
Amanda M
Epicotyl

Cotyledons/Hypocotyl:
Cotyledons: The first leaves of the plant, enclosed inside the seed, the "seed leaves" (Raven, pg. 500) part of the sporophyte generation of the plant, broken into categories such as dicots, monocots, etc. depending on the number of seed leaves present. (Campbell Reece 7th Edition, pg.600)

Hypocotyl: (embryonic stem) grows several inches above the ground, carrying the cotyledons into the light, in which they become green and often leaflike. (Britannica online) The portion of an embryo or seedling situated between the cotyledons and the radicle. (Biology of Plants, Raven, G-12).

The Cotyledons will form the first photosynthetic leaves of the plant in the sporophyte generation. The hypocotyl carries the cotyledons several inches above the ground after the embryo begins to grow so that photosynthesis can begin.
Mark Haywood-Farmer

Cotyledon/Radicle: Both the cotyledon and the radicle are found in the embryo in a seed. The cotyledon is also known as the seed leaf. It is responsible for storing or absorbing food and turns green after the seed has germinated. The radicle is also known as the embryonic roots. It is found in the lower portion of the embryo and is the first part of the plant to emerge from the embryo to form the first root of the plant. (Biology of Plants, Raven 7th Edition)

http://cache.eb.com/eb/image?id=72144&rendTypeId=35 Morgan Traverse

Dicotyledon/Monocotyledon:
A monocotyledon (monos in latin meaning one or single) is a plant who’s embryo has one cotyledon(the leaf of an embryo of a seed plant, which at germination remains in the seed or emerges, enlarges and becomes green) often abbreviated as monocot.
The term dicotyledonous is now an obsolete term (now usually referred to as Eudicotyledones) that refers to all angiosperms that are not monocots. Dicots unlike monocots have 2 cotyledons instead of one. (Raven G-14, G-6, http://www.thefreedictionary.com/dicotyledon)- VanessaV

http://cache.eb.com/eb/image?id=72144&rendTypeId=35

Enhancement:
Dicots: leaf veins are netted, 4-5 flower parts, there is a vascular cambium in secondary growth. (ex. Red alder)

Monocots: leaf veins are parallel, 3 flower parts, there is no vascular cambium in secondary growth. (ex. Palm trees)
(Biology, 7th ed., Campbell Reece, pg. 602)
~Quinn

Dormancy/Quiescence (Andrea Chapman) – Dormancy is a life stage of the embryo where cell division stops, and metabolic activity of a seed slows to wait for unfavourable conditions to subside (Vleeshouwers et al. 1995). The seed may not actually be asleep, but is continuously sensing the environment and adjusting its metabolic rate. Another way to describe this phenomenon is that the seed is actively sleeping or sleeping awake. Quiescence is a stage of inactivity the embryo goes through that still allows the processes of cell division to take place (Rensing and Samuels 2004). Quiescence is also a function of environmental conditions. Dormancy and quiescence are both states of inactivity practiced by the embryo that are influenced by environmental changes. The difference is that dormancy is a state of inactivity where cell division ceases, and quiescence is a state of inactivity where cell division still takes place.

Vleeshouwers L.M., Bouwmeester H.L., and Karssen C.M. 1995. Redifining seed dormancy: an attempt to integrate physiology and ecology. The Journal of Ecology 83(6): 1031-1037 URL http://www.jstor.org/view/00220477/di985501/98p01064/0?frame=noframe&userID=ce7bb2ca@tru.ca/01c0a80a6b005015fea5&dpi=3&config=jstor
Rensing K.H. and Samuels A.L. 2004. Cellular changes associated with rest and quiescence in winter-dormant vascular cambium of Pinus contorta. Trees 18: 373-380 URL http://www.springerlink.com/content/hq0ctklf8y4dv2nf/fulltext.pdf
Dormancy/Double Dormancy Dormancy is a special condition that seeds and buds require preferable growing environmental condition to initiate growth (Raven Glossary, pg. 7).It is the state of reduced metabolic activities under conditions of environmental stress or in winter, when such stressful conditions are likely to appear (Encyclopedia Britannica online). Double Dormancy is a combination of seed coat: external dormancy and internal dormancy. To achieve germination with seeds having double dormancy, the seeds must first be scarified and then stratified for the appropriate length of time (NC state university). This means that the double dormancy require simply warm (> 15oC) or cold (1-10oC) conditions during which time the embryo develops and then breaks the dormancy. It also requires extended cycle of cold and warm temperature to satisfy the dormancy (Robert L. Geneve). Dormancy is the state at which seeds’ activities are reduced until they meet their preferable environment. Whereas, double dormancy is the state at which seeds’ activities are stopped in and out and they requires specific environmental conditions to break the dormancy. Tamiki N

Endosperm and cotyledonsReserved food for the developing seed of angiosperms is initially stored in the nutrient tissue referred to as endosperm. In many eudicots these tissues are reduced to nothing as the embryo absorbs these nutrients to develop fleshy cotyledons, which stores the nutrients through dormancy and then will nourish the seedling as it resumes growth. An example is the garden pea. Some eudicots maintain the endosperm to be absorbed by the cotyledons until after germination. Seedlings obtain nutrients from the endosperm by way of the cotyledon. (Biology of Plants, Raven, p 503-504, 450) Kirsten Jorgensen

Growth regulators/embryo immaturity: Growth regulators:(Science: plant biology) substances that, at low concentration, influence plant growth and differentiation. http://www.biology-online.org/dictionary/Phytohormones Embryo Immaturity: Dormancy introduces a temporal delay in the germination process that provides additional time for seed dispersal over greater geographical distances. It also maximizes seedling survival by preventing germination under unfavourable conditions. http://4e.plantpys.net/article.php?ch=t&id=8 This type of dormancy is biochemical or morphological. Both are a form of dormancy which result from the embryo. Growth regulators use phytohormes in order to postpone dormancy until further environmental factors have been met, this is a physiological factor. Embryo immaturity dormancy is both a physiological factor as well as a physical factor. The physiological factor is the biochemistry of the embryo, and the physical factor is the morphology of the embryo such as size. In order to break growth regulators a decrease of temperature is needed or stratification, or exposing the seed to light. In order to break immaturity dormancy the period of afterrippening is needed. Most common causes of dormancy in seeds are the physiological immaturity of the embryo( Biology of Plants, Raven, p. 504)-Amanda Last

Douglas Fir cones(left)an example of a seed that has a dormant embryo resulting from hormones. Picture from: http://www.jungleseeds.com/images/DouglasFir.jpg
Ginkgo seeds(right) an example of a seed that has a dormant embryo resulting from immaturity.
http://upload.wikimedia.org/wikipedia/commons/thumb/a/a3/Ginkgo_biloba0.jpg/180px-
Added by: Amanda Last

Endosperm/Megagametophyte-Danielle Dornik

Endosperm	Megagametophyte
• In Angiosperms • Located within the seedcoat • Surrounds and nourishes embryo • Stores starch fat and protein • Also provide nutrients for humans	• In gymnosperms • Located within the ovule • Food supply and support for embryo • Mainly carbohydrates and fats

Endosperm/Megagametophyte Enhancement

To enhance this table I wanted to clarify that both the megagametophyte and endosperm is the origin of stored food for the developing ovule. Although the female gametophyte, the megagametophyte, provides the stored food in gymnosperms and the endosperm is nutrient tissue that provides stored food in angiosperms. The endosperm is not gametophytic nor sporophytic tissue and also differs by forming before fertilization. (Biology of Plants, Raven, p 450.) kirsten jorgensen

Angiosperm and Gymnosperm seed

Biology Of Plants, Peter H. Raven, Encyclopedia Britannica (http://www.britannica.com/eb/article-9032623/endosperm)

Hypocotyl/Epicotyl

Hypocotyl The equivalent of the stem in a young seedling. The vegetative organ between the root and the cotyledons, which is responsible for initial upward elongation growth.www.nature.com/nrm/journal/v3/n2/glossary/nrm728_glossary.html. The part of a plant embryo in a developing seed just below the cotyledons, from which the primordial root develops. Dictionary of Natural Resource Management (P.167) Epicotyl-In plant physiology, the epicotyl is the embryonic shoot above the cotyledons. In most plants the epicotyl will eventually develop into the stem and the leaves of the plant. In dicot, the hypocotyl is what appears to be the base stem under the spent withered cotyledons, and the shoot just above that is the epicotyl. The hypocotyl is what develops into the roots of the plant. In monocot plants, the first shoot that emerges from the ground or from the seed is the epicotyl, from which the first shoots and leaves emerge. http://www.answers.com/topic/epicotyl. The stem of axis of a germinating seedling above the cotyledons. Dictionary of Natural Resource Management.(p111)R.Swite

Figure 1 picture showing the placement of a hypocotyl
and a epicotyl during seed germination.R.Swite
cache.eb.com/eb/image?id=63287&rendTypeId=4 The epicotyl and hypocotyl are both very important in the development of plants during seed germination. The epicotyl is responsible for the upward growth of the plant developing into the stem and leaves, which are responsible for the photosynthetic properties of the plant. The hypocotyl is responsible for roots and anchoring of the plant which aid in the nutrient uptake. Both of these properties of the plant are very important because they both aid in the plants survival rate when the plant is at a vulnerable state. RSwite

Megagametophyte/Microgametophyte Megagametophyte is the haploid female gametophyte. Haplolids give rise to a diploid zygote. (Seeds: Physiology of Development and Germination, Bewley, p 29) Microgametophyte is the haploid male gametophyte. An example is the pollen grain in gymnosperms. (Plant Function and Structure, Greulach, p 408). Kirsten Jorgensen
Enhancement to Megagametophyte/Microgametophyte (Caitlin Deas) This picture shows the life cycle of an angiosperm, including both the microgametophyte and the megagametophyte. (Encyclopedia Britannica Online) http://images.google.com/imgres?imgurl=http://cache.eb.com/eb/thumb%3Fid%3D5612&imgrefurl=http://www.britannica.com/eb/topic%3FidxStructId%3D380405%26typeId%3D17&h=88&w=100&sz=6&hl=en&start=4&tbnid=8oviQP_3-D4WAM:&tbnh=72&tbnw=82&prev=/images%3Fq%3Dmicrogametophyte%26gbv%3D2%26svnum%3D10%26hl%3Den%26sa%3DG

Megagametophyte/ Nucellus:
Megagametophyte: An eight-celled megagametophyte called the embryo sac produces the egg. (The prefix mega- denotes gametophytes emanating from female reproductive organs.) (Britannica online) A plant body or cell lineage, formed by vegetative growth of the megaspore, that produces the female gametes of a heterosporous plant.( http://cancerweb.ncl.ac.uk/cgi-bin/omd?megagametophyte) A gametophyte that develops from a megaspore; a female gametophyte(Oxford English Dictionary)
Nucellus: The undifferentiated tissue of the ovule, in which the embryo sac develops.(Oxford English Dictionary) The central body of the ovule that encloses the female gametophyte; equivalent to the megasporangium.( http://glossary.gardenweb.com/glossary/nucellar.html)a The nucleus of the surviving megaspore divides repeatedly by mitosis and a multicellular megagametophyte composed of thousands of haploid cells is produced within the enlarged megaspore. Within the megagametophyte archegonia develop, which contain a large central egg cell.( http://www.umanitoba.ca/Biology/lab8/biolab8_3.html)
Both the megagametophyte and the nucellus are part of the female generation. In order for the megagametophyte to develop the nucellus is needed. The tissue which allows the embryo sac to develop is produced by the nucellus which is then the location where the megagametophyte develops. The megagametophyte produces the egg. Both are needed for the growth and the development of the seed. Amanda Last
Plumule/Cotyledons The Plumule is the first bud of the embryo, it is visible usually just above the cotyledon attachment spot. (Raven, Biology of Plants, p. G-18) Cotyledons are the embryo’s first leaves; they are generally active in absorbing food in monocotyledons and can store the embryonic food in some angiosperms. (Raven, Biology of Plants, p.G-6) The cotyledons are involved in the initial nutritive uptake of the embryo, and emerge from the seed, generally becoming the first green photosynthetic organ. In comparison the plumule (Made up the epicotyl and immature leaves) does not have any involvement in the nutritive uptake of the embryo until it has emerged from the seed when the immature leaves become photosynthetic. The plumule’s leaves will emerge and become photosynthetic after the cotyledons. (American Heritage Science Dictionary, http://dictionary.reference.com/browse/ (Plumule or Cotyledon) The cotyledons and part of the plumule are similar in the sense of being the embryo’s first leaves, and both are situated very close in proximity. Jake

Plumule and Radicle (Kristie Seaborn)

PlumuleThe part of a plant embryo that develops into the shoot system, consisting of the epicotyl and first leaves (Oxford English Dictionary). This embryonic shoot is the first bud (Biology of Plants pg. 503).

Radicle The part of the embryo of a plant which develops into the primary root (Oxford English Dictionary). Located at the end of the hypocotyl, with distinct root characteristics (Biology of Plants pg. 503).

Both of these are found in the embryo. The plumule is found above cotyledons and the radicle is found below the cotyledons. Both axis consist of an apical meristem, and are initial primary growth of both the shoot (Plumule) and root (Radicle) system.
Primary and Secondary seed dispersal (Nicole L) Primary seed dispersal is the initial movement of a seed away from its parent tree. Secondary seed dispersal is the movement after the initial movement of that seed by a different mechanism (ex. wind, water, animals, snow) Both are methods of a seeds movement away from its parent tree.
(http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=154791)

Primary seed dispersal/Secondary seed dispersal: (Mallory Hazell) –
Primary seed dispersal refers to the airborne movement of seeds from a mother plant to the ground surface. A seed may be blown along the surface until it germinates, until it is permanently entrapped or until it’s dispersal structure has deteriorated. (http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1365-2745.2005.01018.x) Where as secondary seed dispersal is seed dispersal that occurs whenever a seed is dispersed in two or more different dispersal events, so that different dispersal agents (e.g. animal frugivores or invertebrates) contribute to different events. Involves movement away from the existing population of trees . (http://www.ingentaconnect.com/content/bsc/jecol/2007/00000095/00000006/art00022)
Quiescence/Growth Regulators: Quiescence and Growth Regulators are both different types of dormancy imposed on seeds. Dormancy is used so a seed will know when it is the optimal time to germinate. Growth Regulators is a dormancy that is brought on by phytohormones that will inhibit growth. It is broken by low temperatures or by light. Quiescence is a dormancy that is imposed by low temperatures but then broken by warm. http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1065910 http://www.amjbot.org/cgi/content/full/89/5/766 --John

Scarification and Stratification (Kristie Seaborn)

Scarification Mechanical abrasion or breaking down of the seed coat by a knife, file, or sandpaper that may allow the “hard seed” condition or inhibitor to be removed or it may permit the metabolic activity requisite for germination to be initiated (Biology of Plants pg. 637).

Stratification is artificially overcoming a seed's dormancy by placing it in layers of moisture-retaining media (paper towel, potting soil, etc.) and keeping it under generally cool and moist conditions for a period of time. This will simulate winter conditions (http://www.emmitsburg.net/gardens/articles/adams/2002/stratification_of_seeds.htm)

Both of these are horticulture practices that initiate germination. In the case of scarification the seed coats are actually being physically broken down by a human hand. But in the case of stratification horticulturists are trying to simulate real environmental conditions.

Enhancement:
This is Scarification

http://www.seabean.com/grow/jpg/Dremelwork.jpg

This is Stratification

http://asgap.org.au/gif/pregerm1.gif

--John

Seed Coat Dormancy/Seed Coat Impermeability (Caitlin Deas)
Seed coat dormancy: Either seed coat impermeability or chemicals in the seed coat can impose seed coat dormancy. In the case of chemicals in the seed coat, leaching of the chemical inhibitors breaks dormancy. This occurs often in desert plants, since germination after a rainfall improves the seed’s chances of survival. Seed coat impermeability is just one type of seed coat dormancy. It refers just to the impermeability of the seed coat, not to chemical inhibitors. This type of dormancy is broken by scarification, which is the mechanical, chemical, or thermal “roughing up” of the seed coat to allow the seed inside to germinate. Sometimes, this scarification occurs by tumbling the seed in a river or by extreme heat.
Biology of Plants, 7th edition, Peter H. Raven, 505
North Carolina Cooperative Extension (NC State University)
http://www.ces.ncsu.edu/depts/hort/hil/hil-8704.html

Seed Coat/Pericarp
(Lacey L) Seed Coat: The outer layer of a seed that is developed from the integuments of the ovule (Biology of Plants, Raven, pg.410 ). It is the protective layer of a seed that is usually hard and often thick. Can also be called a testa. (http://dictionary.reference.com/browse/seed%20coat)

Pericarp: The tissue that arises from the ripened ovary of a fruit(Biology of Plants, Raven, pg.326).The fruit wall, which sometimes in fleshly fruits it can be divided into three layers: the exocarp, mesocarp, and endocarp. For example, in a peach, the skin is the exocarp, the yellow flesh is the mesocarp, while the stone or pit surrounding the seed represents the endocarp. (http://dictionary.reference.com/browse/pericarp)

Summary: The seed coat and the pericarp are similar in that they both are protective covering of a seed of a fruit or a seed. They are also similar because they both are the developed from the ovary. They are different in that the seed coat is the outer layer of a seed where the pericarp is the fruit wall. They are also different because the pericarp can sometimes be layered and the seed coat cannot.
Quiescence/ Seed Coat Dormancy:
Seed coat dormancy is a type of dormancy that is imposed by physiological factors that can be broken by leaching for example in some desert plants the seeds will germinate when sufficient rainfall leeches away the inhibitors in the seed coat. Quiescence is a form of dormancy imposed by physical factors that can be found in Douglas firs, and alders that is brought on by low temperatures and is broken by an increase in temperature. The similarities are that both are forms of dormancy that inhibit germination until more favourable conditions are present, while they differ by how the forms of dormancy are initiate.
Ref:
Biology of plants, pg. 505
http://www.seedbiology.de/dormancy.asp
-Scott Horley

Serotiny/Quiescence (Nikki Heim)

Serontiny: A type of embryo dormancy behavior that occurs for seeds late in developing. It involves a seed case requiring heat, often fire, to open cone and release seed. Cones can remain closed for a year a more after the seeds are mature. (Glossary: Russell M. Burns and Barbara H. Honkala)A common example using serotinous dormany behaviour is lodgepole pine having cones that release seed during occurrence of fire.

Quiescense: A type of embryo dormancy behavior imposed by an external unfavorable environmental factor or external structure.(Seed Germination and Dormancy) A case of unfavorable conditions is often low temperate. The release of seeds is due to a warming temperate. Douglas fir and alder are two examples of plants that undergoe a quiescense this type of embryo dormany. Both serotiny and quiescence are types of embryo dormancy behaviors which tend to open cones and release seeds in presence of increased temperatures. The significant difference between them is that quiescencent cones release seeds with a warming in tempurature and serotinous cones release seeds in a high degree of tempurature that in nature is only reached by fire.

References:

(Seed Germination and Dormancy) Website accessed: www.biologyreference.com/Re-Se/Seed-Germination-and-Dormancy.html (Glossary: Russell M. Burns and Barbara H. Honkala) Website accessed: http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/glossary/glossary.htm

Serotinous/Seed Coat Dormancy
Serotinous: a pinecone or other seed case that requires heat from a fire to open and release the seed.(www.uwsp.edu)

Seed Coat Dormancy: Some seeds of desert species will germinate only when inhibitors in their coats are leached away by rainfall; this adaptation ensures that the seed will germinate only during those rare intervals when desert rainfall provides sufficient water for the seedling to mature (Biology of plants, pg. 505).

Both serotiny and seed coat dormancy prevent a seed from germinating and hold it in a suspended state of biological activity, however serotiny is broken by fir, and seed coat dormancy is broken by rainfall.
Mark Haywood-Farmer

Strobilus/Catkin A strobilus (commonly called a cone) is a reproductive structure consisting of numerous modified leaves. These modified leaves are home scales, attached along a central axis, that have ovules. They occur on many gymnosperms, but also lycophytes and sphenophytes. (Raven, Biology of Plants, p. G22) A catkin is a conglomeration of flowers all of one sex, in a spike-like shape. Catkins are found only in woody plants. (Raven, Biology of Plants, p. G-4) Catkins are Found in Angiosperm families such as Salicaceae, Fagaceae, Betulaceae, as well as a few others. The flowers are either all male, or all female on one catkin. (The American Heritage Science Dictionary, http://dictionary.reference.com/browse/Catkin) In contrast to catkins, strobili are not made of flowers; they are made of many overlapping scales. They are both similar in the sense of being unisexual. Catkins are found manly in angiosperms whereas, strobili are found mainly in gymnosperms. (The American Heritage Science Dictionary, http://dictionary.reference.com/browse/Strobilus)
Jake

Enchancement

Note the presence of flower parts. All flowers on the catkin are imperfect (only having either pistils or only stamens, not both).
These pistils or stamens are what create the textured appearance on the surface of each catkin.
http://waynesword.palomar.edu/images/catkin4.jpg

Note the strobilus has scales that give it’s texture rather than flowers like with the catkin.
The scales are non living cells.

http://www.biologydaily.com/biology/upload/thumb/c/c3/180px-Largepinecone.jpg
(Ryan T)

Dendrochronology

Grohrmoser — Thu, 29 Nov 2007 16:48:37 CST

bristlecone pine
complacent tree
crossdating
dendrochronology
dendroclimatology
eastern white cedar
false ring
krummholz
Layering
Niagara Escarpment
sensitive - Nick Niddrie
subalpine larch
yellow cedar

DEFINITIONS
Please insert your definitions in alphabetical order

Bristlecone Pine: (Mallory Hazell) A long lived, slow growing tree native to Western United States. It belongs to the family Pinaceae and its scientific name is Pinus aristata Englem. var. It has irregular form and is often used for landscape purposes. Needles in bundles of 5 with a bluish-white color from resin. Bristlecone Pine can be up to 5000 years old.
References: (Trees in Canada. pg. 51) (http://dictionary.reference.com/browse/bristlecone%20pine)

Enhancement:
These pines grow in isolated groves at and just below the tree line. Because of cold temperatures, dry soils, high winds, and short growing seasons, the trees grow very slowly. The wood is very dense and resinous, and thus resistant to invasion by insects, fungi, and other potential pests. As the tree ages, much of its vascular cambium layer may die, in very old specimens often leaving only a narrow strip of living tissue to connect the roots to the handful of live branches.
Reference: Bailey, D. K. 1970. Phytogeography and taxonomy of Pinus subsection Balfourianae. Ann. Missouri Bot. Gard. 57: 210-249.
Scott Horley.

The bristlecone pine (Pinus aristata) is known as one of the oldest living trees in the United States ranging from 1500 to 2,500 years of age. Bristlecone pine has durable wood allowing it to stand for hundreds of years until its root system decays. Bristlecone pine growth is extremely slow, growing only .01 inch’s in trunk girth a year and around 30 feet in height. Picture and information found on: http://www.extension.iastate.edu/news/2005/jan/jan0522.html (Jackie Taylor)

Complacent Tree: a tree that has little annual variation in growth rings that are roughly the same for many years in a row. These trees can be difficult to crossdate because the matching of patterns across the growth rings is hard to do when there is little variation .Referneces: http://www.ltrr.arizona.edu/skeletonplot/sensitivitycomplacency.htm , http://web.utk.edu/~grissino/principles.htm The tree on the left is a tree with complacent tree rings, growth is very uniformed over several years. http://web.utk.edu/~grissino/principles.htm VanessaV
Enhancement: The reason that the rings of complacent trees do not change much over many years is because the factor that limits tree growth remains constant from year to year.
(Laboratory of tree-ring research, University of Arizona: http://www.ltrr.arizona.edu/skeletonplot/sensitivitycomplacency.htm) Katherine Loewen
Crossdating: is done by matching the patterns of different sized rings in the wood of one tree and comparing them to rings in another tree. This technique assigns an exact year each individual tree ring was formed. This information can then be used to date certain things. An example would be taking a sample of wood from a house built a long time ago and crossdating the wood to see exact how old the house really is.
Reference: http://www.ltrr.arizona.edu/lorim/basic.html, Vanessa V Picture from: http://www.ltrr.arizona.edu/lorim/basic.html

Crossdating Enhancement: is a technique that ensures each individual tree ring is assigned its exact year of formation. During years of limited growth (for example, during a drought or as a result of falling ash), a tree will not always form a ring completely around its trunk. If a core is collected from a tree where one or more rings are missing, the age of the tree or the dates of the volcanically induced narrow ring sequence will be too young. Missing rings can be detected by matching the ring-width variation patterns of sampled trees with the ring patterns of other trees growing nearby. (http://volcanoes.usgs.gov/About/What/Assess/MSH-1482.html) Lacey L

Dendrochronology: (AarenS)

From the latin words;
Dendros: Using trees (or the growth rings of trees in this case).
Chronos: Time, or in the case of dendrochronology events in past time.
Ology: The study of.

Dendrochronology is the study of using the growth rings (annular rings) of the cross section of a tree to determine many different events and environmental conditions which occurred or were present during the life of the tree. Information obtainable includes but is not limited to insect outbreaks, past fires, forest stand structures, and climate. Each annular ring represents a year in the life of the tree, and certain physiological responses taken by the tree (poor growth during droughts) as well as physical occurrences (signs of a fire) can be noted. The annular rings of trees that grew in proximity to currently living trees can also be aligned to give information which in some cases spans back thousands of years and has even been conducted with art objects and furniture. (http://www.ltrr.arizona.edu/skeletonplot/introcrossdate.htm) (http://web.utk.edu/~grissino/ltrs/) http://sokl.joensuu.fi/saima/saimapictures/kiekkoisov.jpg

Dendrochronology Enhancement: Botanists, foresters and archaeologists began using this technique during the early part of the 20th century. Discovered by A.E. Douglass from the University of Arizona, who noted that the wide rings of certain species of trees were produced during wet years and, inversely, narrow rings during dry seasons. (http://www.sonic.net/bristlecone/dendro.html)Lacey L

Dendroclimatology - the study of the relationships between climate and tree-growth parameters and their use in the reconstruction of past climates. (www.cru.uea.ac.uk/cru/annrep94/trees/) The study of tree rings to infer past climatic conditions, based on recent growth-climate relations. For example, you may find that over the past 50 years (for which there are very good climate data) that there is a relationship between rainfall and tree-ring width. Thus, if you study a 400-year-old tree and find narrow rings early in its growth, there may likely have been a drought during that time period. (www.plantbio.ohiou.edu/dendro/dendroclime) Mark Haywood-Farmer Dendroclimatology enhancement: The growth of a tree is the result of many complex factors and interrelated biochemical processes. There exsists a relationship between localised conditions and large scale climactic parameters. Growth may be effected by sunshine, precipitation, temperature, wind speed, and humidity in addition to the non-climactic factors like competition, defoliators and soil nutrients.

Eastern White Cedar: Thuja occidentalis, a species of thuja, is an evergreen coniferous tree in the cypress family Cupressaceae, native to the north-eastern United States and south-eastern Canada from central Saskatchewan east to New Brunswick, and south to eastern Tennessee in the Appalachian Mountains.

Unlike the closely related western red cedar, it is only a small tree, to 10-20 m tall and 0.4 m trunk diameter (exceptionally to 30 m tall and 1.6 m diameter). The bark is red-brown, furrowed and peels in narrow, longitudinal strips. The foliage forms in flat sprays with scale-like leaves 3-5 mm long. The cones are slender, yellow-green ripening brown, 10-15 mm long and 4-5 mm broad, with 6-8 overlapping scales. It grows naturally in wet forests, being particularly abundant in swamps where other larger and faster-growing trees cannot compete successfully. It also occurs on other sites with reduced tree competition such as cliffs.
Ref:
-Conifer Specialist Group (1998). Thuja occidentalis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
-Gymnosperm Database: Thuja occidentalis (http://www.conifers.org/cu/th/occidentalis.htm)
Scott Horley.

False ring: (AarenS) An annular growth ring that does not represent a full season of growth and does not always form a complete ring on the cross-section of a tree. False rings can appear as bands of what appear to be latewood, followed by earlywood, followed by true latewood all within the boundaries of a true ring. The cause for this is not always understood, and trees with false rings cannot always be used in dendrochronology.
(http://www.yale.edu/fes519b/saltonstall/trchallenge.htm)
(http://www.answers.com/topic/false-ring?cat=technology)

Image from (http://www.ltrr.arizona.edu/skeletonplot/ringanomalies.htm) shows an example of a false ring.

Krummholz: Krummholz is also defined as treelines or timberlines. As elevation increases, the height of the tree gradually decreases while the spacing between them increases until a point is finally reached where the trees give way to tundra (Britanica Online Encyclopedia) . And therefore, trees grow stuntedly caused by wind. It is found in certain tree species at their upper limit of distribution. In cushion krummholz, Alpine trees exposed to severe wind conditions are wind-pruned to a cushion-like mat (Ariadne's Forest Glossary ). Tamiki N

Web citation: http://www.dred.state.nh.us/divisions/forestandlands/bureaus/naturalheritage/Mt.Cardigan.htm Enhancement (krummholz): A forest of stunted trees near the timber line on a mountain; they can also be called elfinwood (Dictionary.com). Krummholz is German for “twisted wood”, which refers to the more-or-less horizontal growth of trees at wind-swept alpine treeline sites. The twisted horizontal growth occurs when the normally upright tree tip or leader is blasted by wind-driven ice crystals during the winter (Kenai National Wildlife Refuge, “Ancient bent trees at treeline are straightening up, tell of climate change”, Article by Ed Berg). Tessa J

Layering- A form of asexual reproduction, capable by select species such as cedar. Attached branches which are covered in soil can root and survive independently. (Silvic of North America, Burns & Honkala, p 639) Kirsten

Enhancement: Layering it produces adventitious roots and this has the advantage that the propagated portion can continue to receive water and nutrients from the parent plant while it is forming roots.. At a later stage the connection with the parent plant is severed and a new plantet is produced as a result.
Layering is also utilised by horticulturists to propagate desirable plants.
Ref:
Britannica Online
(http://www.britannica.com/eb/article-34645/horticulture)
Wikipedia
(http://en.wikipedia.org/wiki/Layering)

sometimes layering is used in horticulture to grow more trees
(A) Pull branch down for simple layer.
(B) Make wound or cut at bend.(so roots can grow)
(C) Stake tip to hold upright.
extension.missouri.edu/.../hort/g06970.htm
VanessaV
Niagara Escarpment: A long escarpment (a transition zone between different physiogeographic provinces) in the United States and Canada that runs westward from New York State, through Ontario, Michigan, Wisconsin and Illinois. It is composed of the Lockport geological formation of Silurian age(about 443 to 416 million years ago). The escarpment is most famous as the cliff over which the Niagara River plunges to form Niagara Falls, for which it is named and is the most prominent of several escarpments formed in the bedrock of the Great Lakes.

Image: http://en.wikipedia.org/wiki/Image:Niagara_Escarpment_in_Red.png
Ref:
- Niagara Escarpment Commission (http://www.escarpment.org/)
- Steven Dutch University of Wisconsin (http://www.uwgb.edu/dutchs/geolwisc/niagesc.htm)
Scott Horley. Niagara Escarpment Enhancement: The Niagara Escarpment may be the only forest ecosystem with millenium-aged trees. These trees consist of ancient estern white cedars thuja occidentalis. There has been no structured investigation into the location and ages of the oldest trees. Currently, recreational activities pose a threat to the trees of the escarpment area. The escarpment formed during the Ordocian and Silurian periods (420 -445 million years BC) and are compised of limestones, dolostones, shales, and sandstones.

Sensitive Tree: Is a tree which is growing in a spot with low water and nutrients, like the side of a hill. It will be more affected by drought than a complacent tree which grows in a spot with lots of water and nutrients. Its tree rings will be more varied with yearly growth. It would be possible to tell which years had lots of rain and which years drought occurred. ( AGU http://www.agu.org/pubs/crossref/2003/2002GL016154.shtml), (URegina http://uregina.ca/~sauchyn/geog411/dendrochronology.html) Nick N
Subalpine Larch: (Mallory Hazell) Also known as the Alpine Larch. A medium sized coniferous tree that is native to northwestern North America. It belongs to the family Pinaceae and its scientific name is Larix lyallii Parl. It is closely related to Larix occidentalis. which is the Western Larch. The Subalpine Larch grows at high elevations above 1500m in the Rocky Mountains. It grows well in acidic or gravelly soils and has irregular form and densely hairy twigs.
references: (Trees in Canada. pg. 72) ( http://dictionary.reference.com/browse/subalpine%20larch)

Note the clusters of needles and how the cones are attached directly to the branch. These are two main characteristics in identifying the Sub-Alpine Larch. It’s distribution range is fairly limited with populations mainly in remote demanding environments. The high mountains of the inland Pacific Northwest, namely the Rocky Mountains and the Cascades, are ideal locations for Sub-Alpine Larch growth.
Images found on Oct 22, 2007 from http://www.nearctica.com/trees/conifer/tsuga/Llyal.htm
(Ryan T)

Subalpine Larch, Enhancement Subalpine Larch Larix lyallii is a deciduous coniferous that grows 10 – 25 m tall producing tough timber. The trunk is sturdy, short and straight, to 30 – 60 cm in diameter. Larix lyallii is distinguished from the lower elevation Western Larch Larix oxidentalis by the wooly hairs that cover its buds, young twigs and lower cone scales. Its needles are square in cross-section rather than triangular as in western larch. Larix lyallii often grows on sites that are too cold for most trees (Plants of Southern Interior British Columbia, Parish, pg. 33)(Oxford English Dictionary).

Enhancement: Most subalpine larch that are larger than about 30 sm in diameter have extensive heart rot. However, if 50- year average radial increments are plotted for individual trees, against date, reasonably horizontal lines result. (Worrall, J. "Subalpine Larch: Oldest Tree in Canada?." Faculty of Forestry, UBC.) htese results show that despite the rotted centers of trees, we can estimate the width of the growth rings within these trees and then get a rough estimate of the age of these trees. If we do so, we find that Subalpine Larch could be the oldest trees in Canada. Mark Haywood-Farmer

Yellow Cedar - A medium-sized tree, up to 24 metres tall and 90 centimetres in diameter; has a broad, grooved trunk that spreads out widely at the base. The crown is sharply cone-shaped, with branches that spread out and droop, and have small, loosely hanging branchlets. (Government of B.C., Ministry of Forests and Range- www.for.gov.bc.ca/hfd/library/documents/treebook). This species goes by many common names including Nootka Cypress, Yellow Cypress, and Alaska Cypress. Even though it is not a cedar, it is also often confusingly called "Nootka Cedar", "Yellow Cedar", "Alaska Cedar", or even "Alaska Yellow Cedar". (Gadek, P. A., Alpers Relationships within Cupressaceae sensu lato: a combined morphological and molecular approach. American Journal of Botany 87)
(world's largest Yellow Cedar, Sayward, BC)
-Mark Dinicol

Ehancement: Yellow cedar trees grow on the west coast of British Columbia and prefer wet, deep, and acidic soils. (BC Adventue: http://www.bcadventure.com/adventure/wilderness/forest/yelcedar.htm) Katherine Loewen
Enhancement: Yellow cedar is also found in a small area in Valhalla Provincial Park. This area is an ecological reserve and is one of the only areas where yellow cedar is found in the interior of British Columbia (Valhalla Provincial Park Management Plan 2004).
Evans Creek in Valhalla Provincial Park. Photo by Morgan Traverse -Morgan Traverse

COMPARE AND CONTRAST
Please put your compare and contrast entries below here; first word alphabetical

Complacent / Crossdating: A complacent tree is a tree that shows very little differentiation between the growth rings despite what is occurring in the environment surrounding the tree. Crossdating is the process of matching up tree rings by matching different events that happened in the trees history such as a drought, fire, a breakout of some kind of tree disease and etc. What happens is you match up these events and you keep going back in time until you have a timeline for dating a tree part that you find due to different disturbances that the tree has seen. A complacent tree will make it very hard to crossdate anything because the disturbances do not show up in the tree rings.

An illustration of the crossdating of the matching of three cores.

A complacent set of tree rings.
http://web.utk.edu/~grissino/principles.htm (Ultimate Tree Ring Page), http;//www.dendro.cornell.edu/svn/corina/trunk/Manual/DocBook/5-Crossdating.chap (Cornell), Liz Foster

Cross-dating/Dendroclimatology Dendroclimatology is the science that uses tree rings to study present climate and past climate. Cross dating is the matching of tree rings to create a timeline, by doing this you can date old structures or the date of when there was a sudden change in climate. By using cross dating you can determine the conditions for tree growth hundreds of years ago, and the climate of that time. (http://www.ltrr.arizona.edu/lorim/basic.html), (http://web.utk.edu/~grissino/principles.htm) Nick N

Crossdating/ False Ring
Crossdating: matching the patterns of different sized rings in the wood of one tree and comparing them to rings in another tree. This technique assigns an exact year each individual tree ring was formed. This information can then be used to date certain things. An example would be taking a sample of wood from a house built a long time ago and crossdating the wood to see exact how old the house really is. (http://www.ltrr.arizona.edu/lorim/basic.html)

False Ring: An annular growth ring that does not represent a full season of growth and does not always form a complete ring on the cross-section of a tree. False rings can appear as bands of what appear to be latewood, followed by earlywood, followed by true latewood all within the boundaries of a true ring. The cause for this is not always understood, and trees with false rings cannot always be used in dendrochronology. (http://www.yale.edu/fes519b/saltonstall/trchallenge.htm)

Crossdating is the use of rings to match the ages of two different trees, false rings often interfere with the pattern of rings in a given tree, and make this tree unusable in dendrochronology and crossdating.
Mark Haywood-Farmer

Dendrochronology/ False Ring: A false ring is a ring of growth in a tree that does not display a full year of growth and often does not display a full year of growth. These false rings are due to significant stress during the growing season. These false rings can appear to be true tree rings and this makes it difficult to use trees with false rings in crossdating. False rings are bands of what appears to be latewood followed by early wood and then followed by the real latewood, all within a true growth ring. Dendrochronology is the study of dating a wooden object by its growth rings. These growth rings are influenced by many of the events in the trees life and are distinctive. This is one of the most reliable ways to date an object. The false rings of a tree will make it really hard to use dendrochronology to date an object because the false rings appear to be true growth rings. A picture of a good tree to use for dendrochronology dating. Liz Foster http://www.yale.edu/fes519b/saltonstall/trchallenge.htm (Yale), http://www.livius.org/de-dh/dendrochronology/dendrochronology.html (Livius), http://www.answers.com/topic/false-ring?cat=technology (Answers).

Dendrochronology/ Dendroclimatology
Dendrochronology: the study of using the growth rings (annular rings) of the cross section of a tree to determine many different events and environmental conditions which occurred or were present during the life of the tree.(http://www.ltrr.arizona.edu/skeletonplot/introcrossdate.htm) Dendroclimatology: the study of the relationships between climate and tree-growth parameters and their use in the reconstruction of past climates. (www.cru.uea.ac.uk/cru/annrep94/trees/)

Both dendrochronolgy and dendroclimatology are studies about the past using tree gowth rings, however, dendrochronology studies events that occured that directly effected the tree itself such as fires, where dendroclimatology studies how the growth rings may have been effected by the climate in the area at the time when the tree was growing. Dendroclimatology uses this information to predict how climate has changed in an area over time.
Mark Haywood-Farmer

Dendrochronolgy/Crossdating Dendrochronology is the study of annual tree rings to determine past dates and the chronological placement of past happenings. This can be used to determine such events as historical forest fires, infestations, climate, and much more. Crossdating is using several segements of different trees and matching them up to form a long chain of rings back or forward in time. http://dictionary.reference.com/browse/dendrochronology http://docserver.ingentaconnect.com/deliver/connect/saf/00221201/v39n10/s6.pdf?expires=1193194920&id=40184233&titleid=3830&accname=Thompson+Rivers+University&checksum=5DB61C101C816158007CE06A0FE18478 -- John
Paleobotany/Dendrochronology By Caitlin Deas
Both paleobotany and dendrochronology use ancient plant structures to determine past events. Paleobotany uses fossilized plants, carbon-dating them to determine when these plants lived. This information can be used to deduce what type of plants and animals lived at that time, and therefore what different things happened (such as the plant species supported a herbivore population which in turn supported a human population). Dendrochronology uses tree rings (from dead or alive trees) to determine the time that historical events occurred. Taking a core sample and analyzing it, without adversely affecting the tree, can date a living tree. Tree rings grow at a known rate, so they are a good measurement of time when compared to a structure or artifact that they are near or in. For instance, the number of tree rings added to a tree after a name is carved into the trunk tells us how long ago the name was carved. Pictures below. (Biology of Plants, 7th edition, Peter H. Raven, 9, 596; http://dendro.cornell.edu/whatisdendro.php)

Dendrochronology (Caitlin) http://en.wikipedia.org/wiki/Image:Tree.ring.arp.jpg

Paleobotany (Caitlin) http://www.ucmp.berkeley.edu/IB181/VPL/Pres/PresP/Pres2.jpeg

Krummolz/Sub Alpine larch
Krummolz- Also known as treelines or timberline. It is the basic concept that as elevation increases the heights of the trees decrease. The spaces between the trees also increase until a point is reached and the tundra takes over. Krummholz is also defined as treelines or timberlines. (Ariadne's Forest Glossary ).
Sub Alpine Larch- The Subalpine Larch grows at high elevations above 1500m. It grows well in acidic or gravelly soils.(Trees in Canada. pg. 72)Subalpine Larch is a deciduous coniferous that grows 10 – 25 m tall. The trunk is sturdy, short and straight, to 30 – 60 cm in diameter. Sub Alpine Larch often grows on sites that are too cold for most trees (Plants of Southern Interior British Columbia, Parish, pg. 33) In comparing these two, one is able to note the effects both have on one another. It shows that the larch is affected by Krummolz and is only able to grow up to a certain elevation.

Sensitive/complacent trees (Daniel Struthers):Tree ring Growth of sensitive trees has many variables, while complacent trees have little variation in tree ring thickness from year to year. The growth of the tree rings depends on the conditions of the environment and how the tree species copes with it. (Science and Technology in Historic Preservation, Ray A. Williamson, Paul R. Nickens, Pg.91)
Sensitive tree growth includes High degree of annual variation, wide and narrow rings intermixed through time, limiting growth factor (e.g., rainfall) is highly variable year to year, sensitive ring growth can be easy to crossdate. Complacent tree growth includes low degree of annual variation, rings are roughly the same for many consecutive years, limiting growth factor is not variable from year to year, and complacent ring growth can be difficult to crossdate.
(University of Arizona:http://tree.ltrr.arizona.edu/skeletonplot/sensitivitycomplacency.htm )

Subalpine Larch/ Bristlecone Pine
Bristlecone Pine: A long lived, slow growing tree native to Western United States. It belongs to the family Pinaceae and its scientific name is Pinus aristata Englem. var. It has irregular form and is often used for landscape purposes. Needles in bundles of 5 with a bluish-white color from resin. Bristlecone Pine can be up to 5000 years old.
References: (Trees in Canada. pg. 51) (http://dictionary.reference.com/browse/bristlecone%20pine)
Subalpine Larch: A medium sized coniferous tree that is native to northwestern North America. It belongs to the family Pinaceae and its scientific name is Larix lyallii Parl. It is closely related to Larix occidentalis. which is the Western Larch. The Subalpine Larch grows at high elevations above 1500m in the Rocky Mountains. It grows well in acidic or gravelly soils and has irregular form and densely hairy twigs.
references: (Trees in Canada. pg. 72) ( http://dictionary.reference.com/browse/subalpine%20larch)
Both trees are members of the family Pinaceae. They are slowing growing trees found in higher elevations. The Bristlecone Pine has 5 needles per bundle while the Subalpine Larch has as many as 30-40 needles per bundle. The cones are also distinctively different as the Bristlecone Pine has shiny smooth cone scales while the Subalpine Larch has rougher, bristle-tipped scales. (Matti Harper)

Yellow Cedar and Eastern white Cedar Eastern White-Cedar (Chamaecyparis nootkatesis): Eastern white-cedars have dull yellowish-green and 1-2mm long scale-like leaves. Twigs are stiff, flattened and covered by yellowish-green leaves. Seed cones are oval shape and leathery scales. Barks are shiny reddish-brown when young, separating into long, narrow, flat gray strip as matured. Eastern white-cedars are small trees which generally grow up to 15 m high and 30 cm in diameter. Trunks are tapering rapidly and often leaning. Roots are shallow and wide spread. Their distribution is south east Canada and north east states.
Yellow Cedar/ Western Red Cedar
The yellow cedars scale-like leaves resemble those of western red cedar, but the scales are all alike, so the leaf-covered twigs appear 4-sided rather than flat. Yellow cedar have rounded cones as opposed to ellictical cones like the western red cedar(Plants of Southern Interior British Columbia, Parish, pg. 48).

Yellow Cedar (Thuja occidentalis L.): Yellow cedars have ever-green; small, dull bluish-green and up to 3mm long leaves. Twigs are very flexible, slightly flattened and green to reddish-brown along stem. Seed cones are berry-like and soft. Barks are thin, scaly grayish-brown when young, separating into narrow intersecting ridges as matured. Yellow cedars are medium-sized tree which grow up to 25 m high and 90 cm in diameter. Trunks are tapered associated with broadly buttressed and fluted base. Roots are shall to deep. Their distribution is along west coastal British Columbia.

Distinctive differences between yellow cedar and eastern white-cedar are their size, seed cone shape and especially their distribution. Moreover, yellow cedars have buds, whereas eastern white-cedars do not. Tamiki N

Yellow Cedar (Chamaecyparis nootkatensis). This is an example of the yellow cedar. (www.ac.wwu.edu/.../yellowcedar.jpg) Matti Harper

Enhancement: By Conyr A.

This is an image of a western red cedar (Thuja Plicata) branch (image from The Forestry Commission of Great Britain webpage at the address http://www.forestry.gov.uk/images/Western-red-cedar.jpg/$FILE/Western-red-cedar.jpg)

Bristlecone Pine/ Yellow Cedar

(LaceyL)

Bristlecone Pine: Small slow-growing, soft pine found in Western coastal areas. Its scientific name is Pinus aristata. It is one of the oldest living trees known and can grow on poor dry soils. It is planted for landscape purposes and can grow from 6 to 12 meters tall (Trees of Canada, Farrar, pg 51, Textbook of Dendrology, Harlow and Harrar, pg 120). Yellow Cedar: : A western species, occurring mainly near the Pacific coast. It is planted for landscape purposes because of the attractive crown with long sweeping principal branches and drooping secondary branches. It belongs to the family Cypressaceae and its scientific name is Chamaecyparis nootkatensis. Its leaves are scale-like and have a dull bluish-green color to them. The Yellow-cedar can also be known as: Alaska cedar, Nootka-cypress, Nootka false cypress, or yellow cypress (Trees of Canada, Farrar, pg.28). It also grows to be up to 24 meters tall and can be 90cm in diameter. Some uses of the trees are boat building, ceremonial masks, paddles and dishes. The bark can also be used for clothing and blankets (http://www.bcadventure.com/adventure/wilderness/forest/yelcedar.htm).Even though the Bristlecone pine and Yellow cedar are from different families (Bristlecone-Pinaceae and Yellow Cedar-Curessaceae) they have similar qualities. Some similarities are that they are both found in west coast areas and they both have a pale bluish color to them. They are also both slow growing species and are used for landscape purposes. These trees are different in that the Yellow cedar can grow up to 24 meters tall where the Bristlecone pine can only grow to be between 6-12 meters tall. Another difference is that the Yellow Cedar requires plenty of moisture to grow where Bristlecone pine can be found in poor, dry soils.

Introduction to Dendrology

Jessi.E.W — Thu, 29 Nov 2007 15:56:16 CST

Terminology on this page will relate to the first lecture which is an overview of the study of Dendrology.
The terminology words from this lecture are:

Note: all these words have been used for definitions

annual - Kristie S
Berry Nicole L
biennial - Kristie S
dendrochronology
dendroclimatology
dendrology
horticulture
Incomplete Flower- Conyr A
Lanceolate leaf shape- Conyr A
leaf area index
McAbee fossil bed
mycorrhizal fungi Ryan T
naval stores
net primary production
paleobotanyRyan T
perennial
petiole - stephanie lauer
pinna - VanesaV
pome - Conyr A
prickle
rachis Jessi.E.W
recurved
reflexed
root graft
Schizocarp- Conyr A
thorn
tree
urban forestry

DEFINITIONS
Please insert your definitions in alphabetical order.

Annual (Kristie Seaborn) A plant that completes its life cycle in a single year or growing season. (Biol. Concepts and Connections 4th ed. Pg. 628). The stem is also a photosynthetic organ (Biology of Plants, Pg. 6). The formation of flowers, fruits, and seeds rapidly depletes food reserves and the vegetative portion of the plant usually dies. Although the exhaustion of food reserves often accompanies death of the plant, it is not necessarily the
cause of death.(Encyclopedia Britannica)

The Alpine wallflower (Erysimum linifolium) is an example of an annual plant.

Picture From: http://www.paghat.com/images/wallflowerbuds_apr.jpg
(Photo added by Jessica W) Enhancement- A true annual is a plant that completes its life cycle in one year. This means it goes from seed to seed and then dies off, during the course of one growing season. The whole mission of an annual is to produce seed and propagate. That's why deadheading or removing spent flowers before the seed matures, produces more flowers and therefore more potential seed. Some tender perennials are grown as annuals in colder climates. For a perennial to be worth growing as an annual, it must flower profusely in its first year of growth. Pansies, lantana and alyssum are all actually tender perennials. There are also plants considered to be hardy annuals. This just means that they are able to withstand a little frost without being killed off and will continue to bloom and set seed into the next year, but they will eventually expire. http://gardening.about.com/od/annuals/g/Annual.htm. R.Swite

Berry -Nicole L A simple fleshy fruit that includes a fleshy ovary wall and one or more carpels and seeds; examples are the fruit of grapes, tomatoes, and bananas (Biology of plants, 7th edition, Raven, p G-3) any small, usually stoneless, juicy fruit, irrespective of botanical structure, as the huckleberry, strawberry, or hackberry. a simple fruit having a pulpy pericarp in which the seeds are embedded, as the grape, gooseberry, currant, or tomato. (Dictionary.com http://dictionary.reference.com/browse/Berry)

Image from http://www.vegparadise.com/images/halftomato.jpg

Biennial (Kristie Seaborn) A plant which springs from seed and vegetates one year (or growing season), and flowers, fructifies, and perishes the next season (Oxford English Dictionary). Beets and carrots are biennials, but we usually harvest them in their first year and miss seeing their flowers ( Biol. Concepts and Connections 4th ed. Pg. 628).

Enhancment: A plant that normally requires two growing seasons to complete its life cycle, flowering and fruiting in its second year.
(Raven EE, glossary) Amanda Last

Picture of a carrot plant, which is an example of a biennial plant.

Picture from: http://content.answers.com/main/content/wp/en-commons/thumb/7/73/200px-Parsley_Curled.jpg
(Photo added by Amanda Last)
Enhancement: These plants are usually herbaceous. During the first season, food is accumulated, usually in a thickened root (beets, carrots); flowering occurs in the second season. As in annuals, flowering exhausts the food reserves, and the plants die after the seeds mature (Encyclopidia Britannica online). Tamiki N

Dendrochronology: 1928 A. E. DOUGLASS Climatic Cycles & Tree Growth II. 5 We are measuring the lapse of time by means of a slow-geared
clock within the trees. For this study the name ‘dendro-chronology’ has been suggested, or ‘tree-time’. This expression covers all the dating and
historic problems..as well as the study of cyclic variations and the distribution of climatic conditions. 1937 Geogr. Jrnl. LXXXIX. 407 A
dendrochronologist is a man who investigates the climate of the past by measuring the rings of trees. 1937 Proc. Prehist. Soc. III. 321 The modern
ways of pollen-analysis, geochronology and dendrochronology must be applied to settle geologically, once for all, the cultural correlations with Scotland.
1959 Antiquity XXXIII. 238 Undateable except by a rough and ready guesswork calculation from dendrochronological dates.
1969 Nature 15 Nov. 682/1 Radiocarbon measurements carried out on dendrochronologically dated wood samples.(Oxford English Dictionary).
Amanda Last.

Picture illustrating growth rings on a tree which are related to both dendrochronology and dendroclimatology.

Picture from: http://www.idahoforests.org/img/cookie2.gif
(Photo added by Amanda Last)

Dendroclimatology:The study of past climates by the examination of the annual growth rings in (ancient) timber.
1953 E. SCHULMAN in Tree-Ring Bull. XIX. 22 It is important in both dendro-climatology and dendro-archaeology to consider the frequency
of occurrence and areal distribution of non-usable ring series in species commonly suitable for such analysis. 1978 Nature 4 May 40/2 This has been
undertaken to obtain past climate information from the isotope ratios of the hydrogen, oxygen and carbon isotope ratios in the various constituents
of wood by workers in the embryonic science of isotope dendroclimatology. 1981 New Scientist 19 Feb. 462/1 Dendroclimatology is a young but
increasingly important branch of science. Tree rings are, in effect, a ‘diary’ of weather in the past. (Oxford English Dictionary) Amanda Last.
Enhancement: In order to examine the natural growth rings of trees without killing them is to extract a drinking straw sized core sample. This sample is obtained by use of an increment borer. http://www.dnr.state.wi.us/org/caer/ce/eek/job/images/foresterQuizCoreBorer2.jpg - Morgan Traverse

Dendrology - The study of woody plants. These woody plants usually consist trees shrubs and vines. Trees are a woody plant usually having one central
trunk while shrubs may have many woody stems. This list also includes vines which are woody plants that require the support of another tree or
abiotic structure. Woody plants do not belong to many different families but some non woody plants also belong to these families. Dendrology comes
from the latin name dendro, meaning tree and ology meaning the study of, hence the study of trees. Dendrology usually focuses more towards the species
that are used wider economically. (http://botit.botany.wisc.edu/courses/dendrology/) Mike Tomlinson

Horticulture: The art or science of growing flowers, fruits, or vegetables, etc. (Gage Canadian Dictionary, Pg. 564) Art or science of
cultivating gardens. (Collins English Dictionary, Canadian ed. Pg. 202). Some examples of horticultural work are plant and crop
production, breeding of plants, genetic engineering of plants, and the study of the physiology of plants.

Enhancement:
Latin- Hortus (garden) + cultura (culture)
Horticulture is a subdivision of agriculture dealing in gardening
(Jules. 1979. Horticultural science. San Francisco: W.H. Freeman)

-Danielle Dornik

Enhancment: Even though most practices in Horticuture are very ancient (botany ) recent knowledge about genetics, physiology, biochemistry, ecology, pathology, entomology, molecular biology and soils has been put to much use(plant breeding ). And this has turned horticulture into a higely complex science for some people. VanessaV
http://www.encyclopedia.com/doc/1E1-horticul.html

Enhancement (Kevin Christie)

Butchart Gardens in Victoria BC, an excellent example of horticulture.

Incomplete flower: A flower lacking one or more of the four floral parts needed to be considered complete.
The parts missing could be any of the following four:
-sepals found on the outermost part of the flower and are part of the calyx
-petals which are larger than sepals and part of the corolla
-stamens which produce pollen and form the androecium
-carpels which house the ovules and form the gynoecium.
(http://en.mimi.hu/gardening/incomplete_flower.html & of Plants, 7th edition, Peter H. Raven, Glossary Section)

This figure clearly shows the comparison of a complete flower against the incomplete flower which is missing the stamen.
http://images.google.ca/imgres?imgurl=http://extension.oregonstate.edu/mg/botany/images/fig20.gif&imgrefurl=http://extension.oregonstate.edu/mg/botany/flower2.html&h=254&w=470&sz=18&hl=en&start=7&um=1&tbnid=hpAAer285RrfTM:&tbnh=70&tbnw=129&prev=/images%3Fq%3Dincomplete%2Bflower%26svnum%3D10%26um%3D1%26hl%3Den%26sa%3DN Enhancement: An example of an incomplete flower is the blue clematis (Clematis occidentalis). This flower has 4 blue sepals and is missing petals. (Plants of Southern Interior British Columbia and the Pacific Northwest. Parish et. al. pg 210)

Photo by Morgan Traverse.
-Morgan Traverse

Lanceolate leaf shape: A unique leaf shape in which the leaf resembles a lance head, and both ends of the leaves taper to form a point most noticeably at the tip.
The general shape of these leaves is a broader base with a thin pointed tip, and they are longer than they are wide in all cases.
(http://www.thefreedictionary.com/lanceolate+leaf The Free Dictionary by Farlex, http://en.mimi.hu/gardening/lanceolate.html from MiMi.hu

This image shows the general shape of a lanceolate leaf.

Retrieved from Leaf Illustrations by Marina Smelik at http://www.smccd.edu/accounts/leddy/lflance.jpg

(http://www.stcharlesparks.com/128/information/horticulture.php)

Leaf Area Index (LAI): the leaf surface area per surface area of land (using the same measurement units). Broad-leaf forests use only one side of the
leaf when calculating the LAI while needle-leaf stands use the entire leaf surface area. However, if the forest is a mix of both broad-leaf and needle-leaf
forest then a combination of the two are used in the calculation of LAI. ("Glossary". Burns, Russel. M., Barbara H. Honkala. October 16th 2007.
http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/glossary/glossary.htm). Steph L

McAbee fossil bed: A fossil bed of Middle Eocene lucustrine (lake-bed) deposits over 56 million years old, located near Cache Creek British Columbia
(Mustoe 2002). The site includes 87 floral taxa, consisting of Gymnosperms (16 separate species, 14 conifers, and 2 Ginkgos) and 67 different angiosperm
genera (Dillhoff et al. 2005). Andrea Chapman
Enhancement:Over 50 plant varieties have been found, including over 40 Broadleaves and 17 Conifer species. Sassafras, katsura and both
Ginkgo varieties are also present. Countless insect species can be found such as tiny flies, wasps, leafhoppers, etc. The fish Eohiodon (Mooneye),
cones, flowers and even a few feathers also can be found.
(http://www.dll-fossils.com/Index.asp) Krista N

Alder Leaf Eohiodon Rosei Fish Fossil Katsura Leaf

Mycorrhizal fungi: Fungi that benefit their host plants by increasing that plants' ability to capture water and essential elements, especially phosphorus.
In return the plants provide the fungi with organic nutrients. Increase in the absorption of zinc, manganese and copper have also been demonstrated through
Mycorrhizal fungi. (Biology of Plants, 7th ed. Peter H. Raven, Pg. 610) Ryan T

Enhancement: This symbiotic relationship is essential for better tree growth. The Mycorhizal fungi lets trees to increase its surface area for absorption of water and nutrients from soil and increase branches and diameter of infected roots. Trees with the Mycorrhizal fungi absorb nutrients faster than that without the fungi ( Dictionary of Natural Resource Management. p.217). Tamiki N

Naval store: Pine tar and pitch were once used to make the seams of boat water tight and to protect ropes on wooden sail boats. These pine products are
referred to as navel store. The chemicals extracted from pine trees are still used today in the manufacture of inks, adhesives, perfumes and other consumer
products. American Heritage Dictionary. The chemical products of pine trees are turpentine, rosin and fatty acids. The origin of this word dates back to
1670 -80. dictionary.com
Henhancment:
The term now applies to the products that come from the pine tree: pine oil, pitch, tar. There are two classifications of these products, those obtained from living trees and those obtained from dead trees. Most naval stores are produced in the south east United States and Southern Europe. Some fo the most largely manufactured things are soap, paint, varnish, shoe polish, lubricants, linoleum, and roofing material. (http://www.encyclopedia.com/doc/1E1-navalsto.html) VanessaV
Enhancement #2

This picture from 1936 shows how sap was extricated from longleaf pines. (http://www.sherpaguides.com/georgia/fire_forest/cultural_history/index.html)
Liz Foster
NPP (Net Primary Production) - Net primary production is a method used to record and quantify the net absorption of carbon. NPP is the greatest when
the difference between respiration and photosynthisis is the greatest. NPP is an important part of measuring the carbon cycle, to determine how much
carbon is taken up by plant to produce plant growth. If the rate of plant growth is then determined by this process then it can prove to be a very useful
tool in sustainable forest managment. http://www-eosdis.ornl.gov/NPP/npp_home.html (Mike Tomlinson)
Enhancement: (AarenS)

(Derived from notes of John Karakatsoulis slide #39 NRSC 210)

Rachis – The rachis is the central elongated axis of the leaf. In compound leaves the rachis is an extension of the petiole corresponding to the midrib of the complete leaf. (How to Identify Plants, H.D.Harrington, dictionary .com)Jessi.E.W

Root graft: Horticultural - the process of grafting a shoot or a stem of one plant onto a section of root of another. A root graft may also occur as a natural
underground growing together or joining of roots, from two plants. dictionary.com The roots of American Elm ,Ulmus americana, tend to fuse together
(root graft) enabling the spread of Dutch elm disease.
(Kansas State University of Agriculture and Experiment Station Department of Pathology. 2006. google)
Enhancement (Andrea Chapman)
This interconnection produced by a root graft can increase support, stability, and anchorage as well as allow inter-tree translocation of nutrients and water
(Keeley 1988).

Keeley, J.E. 1988. Population variation in root grafting and a hypothesis. Oikos 52: 364-366

Enhancement: This is an example of a root graft from an American Elm. The one pictured is a natrual root graft. -- John
http://images.google.ca/imgres?imgurl=http://www.oznet.k-state.edu/path-ext/factSheets/Trees/treeimages/elmDED3small.jpg&imgrefurl=
http://www.oznet.k-state.edu/path-ext/factSheets/Trees/Dutch%2520Elm%2520Disease.asp&h=221&w=311&sz=28&hl=en&start=5&tbnid=
qcEIhZKlA6kzSM:&tbnh=83&tbnw=117&prev=/images%3Fq%3Droot%2Bgraft%26gbv%3D2%26svnum%3D10%26hl%3Den

Schizocarp: A type of dry simple fruit found in plants, most commonly trees. They are winged and vary in length as well as angle between each set of wings.
They consist of two joined carpels which split at maturity to allow better distribution. Upon maturation and the split the individual sides are referred to as mericaps.
This type of fruit is seen frequently in trees from the genus acer.
(Biology of Plants, 7th edition, Peter H. Raven, G-24, http://www.tiscali.co.uk/reference/encyclopaedia/hutchinson/m0007072.html)

This illustration clearly depicts a shizocarp on the branches of a Norway maple of the genus acer.

http://images.google.ca/imgres?imgurl=http://www.ces.ncsu.edu/depts/hort/consumer/fourh/images/picts/AcerPla1.jpg&imgrefurl=http://www.ces.ncsu.edu/depts/hort/consumer/fourh/images/Acer__3.htm&h=393&w=450&sz=29&hl=en&start=7&um=1&tbnid=Tfg5c3VO0vfSMM:&tbnh=111&tbnw=127&prev=/images%3Fq%3Dschizocarp%26svnum%3D10%26um%3D1%26hl%3Den%26sa%3DN

Paleobotany:The study of paleobotany involves the investigation of the remains of plants and plant pieces in archaeological sites or other landscapes of the
past. Though plant matter doesn't stay unchanged over periods of centuries or millennia, evidence in the form of floral remains such as charred seeds and
phytoliths does remain and can provide information on prehistoric diet and climate (http://archaeology.about.com/od/pterms/g/paleobotany.htm, K Hirst, para 1).
Paleobotany has had a great effect on todays current understanding of the evolution of the major groups of plants, in particular the interrelationships among the
classes of seed plants.("Botany," Microsoft® Encarta® Online Encyclopedia 2007 http://encarta.msn.com © 1997-2007 Microsoft Corporation.) Ryan T
Enhancement(Amanda Last)The branch of botany that deals with extinct and fossil plants.

1872 H. A. NICHOLSON Man. Palæontol. 473 The subject of Palæobotany or Palæophytology. 1935 W. H. TWENHOFEL & R. R. SHROCK
Invertebr. Paleontol. i. 1 Paleontology..may be divided into paleobotany, treating of fossil plants, and paleozoology, treating of fossil animals. 1982
Canad. Jrnl. Linguistics 27 67 He reconstructs the Proto-Indo-European tree terminology in the light of modern palaeobotany. 1991 R. GOLDRING
Fossils in Field iv. 68 Most aerial parts of fossil plants are found as fragmented and dispersed remains. How can these be reassembled as a reconstruction
of the original plant? Palaeobotany is much concerned with this detective work. (Oxford Englsih Dictionary)

Perennial: A plant in which the vegetative structures live year after year. (Biology of Plants 6th ed. Peter H. Raven, Pg. 905) A plant lasting through the
years; recurring perpetually. (Collins English Dictionary, Canadian ed. Pg. 309) Perennial plants may be woody plants or herbaceous. Trees are examples
of woody perennial plants. An example of a herbaceous perennial plant is an Echinacea purpurea, or purple coneflower.

Purple Coneflower - Echinacea purpurea
Photo added by Steph L
("Wildflowers and Native Grasses". Prairie Nursery. October 16th 2007.
http://prairienursery.com/store/index.php?main_page=mag_product_seed_info&products_id=91&zenid=
80b0eaf948fbea7a179443be9a19b180 )
Enhancement Latin= per, “through” and annum, “year”. Perennial plants life cycles can be short lived meaning three years or they can be long lived meaning three thousand years. They may also need several years to grow before they are sexually able to reproduce. (Forest Management Workshop Manual , Duane Bristow, 1995)Jessi.E.W
Enhancement: The perennials differ from herbaceous (iris, delphinium), shrubs or trees in which the storage structures are either permanent or are renewed each year (Encyclopedia Britannica online). Tamiki N
Petiole (Stephanie Lauer)– the leaf stalk (Raven, Biology of Plants, pg G-17). The stalk of the leaf that joins the leaf to the node of the stem (Campbell & Reece, Biology 7th ed, Glossary).

Pinna:(plural pinnae) A primary division (or leaflet) of a compound leaf or frond; it may be divided into pinnules. (Raven G-18) Latin for feather, A leaflet or primary division of a pinnately compound leaf.( http://www.thefreedictionary.com/pinna)

image from: http://www.palaeos.com/Plants/Lists/Glossary/Images/PinnaDavallia.gif -VanessaV

Tree: A perennial woody plant generally with a single stem (trunk). (Biology of Plants 6th ed. Peter H. Raven, Pg.912) A large perennial plant with a
woody trunk. (Collins English Dictionary, Canadian ed. Pg. 441-442). An example of a tree is a Larix occidentalis, or a western larch.

The structures of trees include leaves, bark, roots, and the vascular system. Leaves perform two vital functions for trees. They produce
sugars by photosynthesis and they allow for the distribution of water through transpiration. Bark is the protective layer of the tree which
is extremely useful to fend off pests and disease from entering the tree. Roots are made up of both root hairs, lateral roots and the taproot.
The root hairs are used to take up nutrients and water into the tree and the taproot, as well as, lateral roots keep the tree stationary in the
ground. The vascular system transports the nutrients and water that the roots had taken in. The vascular system is composed of the xylem
and the phloem.(http://www.elmcare.com/trees/structures/structure_of_trees.htm )- Daniel Struthers

Urban Forestry
The care and management of urban forests. The control of tree populations in an urban environment. Urban foresters plant and maintain
trees, support appropriate tree and forest preservation, conduct research and promote the many benefits trees provide. Urban forestry is
practiced by many. Some challenges faced by urban forestry include:

Limited root and canopy space
poor soil quality
deficiency f excess of water and light
heat
pollution
mechanical and chemical damage to trees

(Nowak, D. (2000). Tree Species Selection, Design, and Management to Improve Air Quality Construction Technology)
(http://spacing.ca/wire/?p=2367)

Enhancement (Andrea Chapman)Some of the many benefits of this practice include energy and water conservation, as well as increased inner city wildlife, scenery, and noise buffer values. Two main benefits are the potential to reduce the heating effect caused by urban areas, and the possibility of a heightened psychological effect on humans (Bradley 1995).

Bradley G.A. 1995. Urban forest landscapes: integrating multidisciplinary perspectives. University of Washington Press. Pg 3-5 URL http://books.google.ca/books?id=PfxEX4UkTbEC&printsec=frontcover&dq=urban+forestry#PPA5,M1
Enhancement: Thus urban forests have a substantial monetary benefit to the municipalities, provincial and federal governments (storm water attenuation, air quality mitigation, tourism, health care costs, etc.), to residents (property value, energy conservation, etc.) and business (tree care companies, nursery industry, aesthetics of retail areas). Internationally, many cities are recognizing that their urban forests will play an important role in their competitiveness to attract business and industry (Tree Canada). http://www.treecanada.ca/programs/urbanforestry/benefits.htm Tamiki N

_________________________________________________________________________________
COMPARE AND CONTRAST
Please put your compare and contrast entries below here.
Actinomorphic vs. Zygomorphic Actinomorphic (= regular) flowers are capable of being divided into equal halves along any diameter. An example of this kind of flower is a sun flower. Zygomorphic flowers (= irregular) flowers that are bilaterally symmetrical. A zygomorphic flower can be divided into equal halves along only one line. The flower consists of five petals a banner (one petal), a wings (two petals) and keel (two fused petals). The fruit will develop into a pod. Actinomorphic and zygomorphic are both terms that describe flowers. (dictionary.com, www.wildflower-and-weeds.com) Jessi.E.W

Berry and Pome Both of these structures include seeds, are composed of a flesh like substance and are found on plants. They offer a means of reproduction and a way to increase dispersal.
They can also be relatively close in size depending on the species used in comparison.

Berries are the most common type of fleshy fruit found in plant types. They are composed of one or several carpels found encased in a thin coating.
The seeds of berries are embedded in the flesh of the ovaries, and the ovary of berry producing flowers are superior.
(information from Berry definition on Wikipedia at the address http://en.wikipedia.org/wiki/Berry)

A pome is an accessory fruit which is composed of five or more carpels. The mesocarp of this fruit is generally fleshy and the seed is enclosed by a leathery casing formed by the endocarp.
The ovary of this kind of fruit is inferior.
(information from Pome definition on Wikipedia at the address http://en.wikipedia.org/wiki/Pome)
by Conyr Aird

Enhancement to Berry/Pome (Caitlin Deas)
This is a typical example of a pome. (Iowa State University Department of Ecology, Evolution, and Organismal Biology)
http://www.eeob.iastate.edu/classes/bio366/terminology/fruit/images/apple-pome.jpg

This is a typical example of a berry-the blueberry. (Essential Oil.in) http://www.essentialoil.in/images/blue-berry.jpg

Berry/Schizocarp Nicole L
Berry is a simple fleshy fruit that includes a fleshy ovary wall and one or more carpels and seeds; examples are the fruit of grapes, tomatoes, and bananas (Biology of plants, 7th edition, Raven, p G-3) Schizocarp is a dry simple fruit with two or more united carpels that split apart at maturity (Biology of Plants, 7th edition, Raven, p G-21) Both are a form of fruit on angiosperm trees

http://www.hort.uconn.edu/plants/campus/uconn/dec/walk8/five/apla.jpg
http://www.studioandree.com/images/thumbArbutusFruit.gif

Biennial Plants and Perennial Plants (Jessica Wrench)
A Perennial is a plant in which the vegetative structures live year after year. (Biology of Plants 7th ed. Peter H. Raven, Pg. G-17)
A Biennial is a plant that normally requires two growing seasons to complete its life cycle, flowering and fruiting in its second year.
(Biology of Plants 7th ed. Peter H. Raven, Pg. G-3)

Perennial and biennial plants are similar in that they are both classified as plants and share similar stages in their life cycles. The
difference is that a perennial’s life cycle continues on much longer than the two year life cycle of a biennial plant.Perennial plants include
all trees and shrubs as well as some herbaceous plants that return to ground structures, such as bulbs, in the colder seasons. On the other
hand, biennials include only herbaceous plants. Another difference is that biennials only flower once in their lifetime where as perennials
will flower once every year when they reach maturity.

An Annual is a plant which completes its entire life cycle (growth, flowering and death) in a single growing season. Summer annuals
cycle between spring and fall while winter annuals being germination in the fall and over winter and being their lifecycles in the following
spring and continuing until fall. (Weed Control Glossary. OMAFRA Staff, Novemeber 1999.
http://www.omafra.gov.on.ca/english/crops/pub75/appendx_b.htm) Steph L

Annual plants are also similar to perennial and biennial plants in the sense that they too are a herbaceous plant and also have the same
life cycle but the difference in an annual plant is that an annual only lives for one growing season. In this time, the plant first spends a
series of a few weeks or months accumulating food materials for rapid growth. The plant then matures based on environmental factors
and the plant beings to start producing flowers, fruits or seeds. This production of flowers, fruits or seeds, phyisically drains the plant and
along with other factors beings the process of the end of the plants life cycle. ( "life span." Encyclopædia Britannica. 2007.
Encyclopedia Britannica Online. October 16th 2007. http://www.britannica.com/eb/article-63859/life-span#526769.hook ) Steph L

Biomass/NPP: (Jackie Taylor)
Biomass: Is the total dry weight of all organisms in a particular population, sample, or area. NPP: Net primary production is the rate at which new biomass occurs in an ecosystem.
References: Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-3. http://en.wikipedia.org/wiki/Primary_production

Dendroclimatology /Dendrochronology: Dendroclimatology is the modelling of tree growth variations in relation to weather (Visser and Molenaar 1988).
It can be used to understand how historic climate activities have affected trees, by separating human related and natural climate change events
(Lara et al. 2002). Dendrochronology is a science that analyzes tree rings for various reasons, including dating archaeological and historical structures,
as well as mapping past climates (Cook 1990). Dendroclimatology appears to be a branch of Dendrochronology. Dendrochronology analyzes tree rings
(growth patterns) for reasons ranging from understanding slope movement activities (Braam 1987) to mapping past climates. Where Dendroclimatology
solely focuses only on how climactic changes affected growth patterns. Even though both subjects focus on analyzing growth rings, Dendroclimatology
is more focused on the climate aspect. Andrea Chapman

ANGIOSPERM/ GYMNOSPERM
Angiosperms are flowering plants. Angiosperms are the biggest group in the plant kingdom. They have true roots, stems, leaves and flowers. They also
have seeds.The seeds are formed when an egg or ovule is fertilized by pollen in the ovary. The ovary is within a flower. The flower contains the male
and/or female parts of the plant. Fruits are frequently produced from these ripened ovaries. Angiosperms are more highly evolved that the algae, mosses,
fungi and ferns. Their advanced structures allow angiosperms to thrive on land. They have roots that hold the plant in place and take in needed minerals
and water. They have leaves that are the major food makes for the plant. They have stems that hold the plants up and move the nutrients and water about
the plant. http://www.mcwdn.org/Plants/Angiosperm.html Gymnosperms are woody plants that produce seeds, but, unlike the flowering plants (angiosperms),
the seeds are not enclosed inside an ovary. This means that instead of developing inside a fruit, such as a berry or acorn, gymnosperm seeds are more
exposed. Often they are housed in somewhat open structures called cones. (The seeds, or the structures that contain them, sometimes appear quite similar
to fruits, though, as is the case with ginkgo and juniper trees.)http://www.ibiblio.org/pic/GymnospKey/gymnosperm_description.html.(Summary)The main
difference between the Gymnosperm and the Angiosperm is the fact that the Angiosperms are flowering plants that enclose the seed inside the ovary
producing fruit when ripe The seeds are more protected and developed for life on land. The Gymnosperm seeds are more exposed to the elements and
are often protected in a woody cone. (RSwite)

Braam R.R., Weiss E.E.J., and Burrough P.A. 1987. Spatial and temporal analysis of mass movement using dendrochronology. Elsevier. URL http://igitur-archive.library.uu.nl/fysgeo/2006-1212-202044/UUindex.html

Cook E. 1990. Methods of dendrochronology. Springer. Preface 1. URL http://books.google.ca/books?hl=en&lr=&id=zr8Ucld6FYcC&oi=fnd&pg=PP9&dq=dendrochronology&ots=ZfIg2tNNLJ&sig=WHfgjsR1EI0jmGnkBT2Eu0rogmc#PPP9,M1

Lara A., Aravena J.C., Villalba R., Wolodarsky-Franke A., Luckman B. and Wilson J. 2001. Dendroclimatology of high-elevation Nothofagus pumilio forests at their
northern distribution limit in the central Andes of Chile. Can. J. For. Res. 31: 925-936

Visser H. and Molenaar J. 1988. Kalman filter analysis in dendroclimatology. Biometrics 44: 929-940

Dendrology/Horticulture: Dendrology is a branch of botany that focuses on the study of woody plants, specifically trees (http://www.reference.com/browse/wiki/Dendrology) whereas horticulture is the science of cultivating plants, such as trees, for the purpose of ornamentation or agriculture (http://www.reference.com/search?q=horticulture). - Tori Waites

Horticulture/Urban Forestry (Sarah Slater): Horticulture is the science of producing and managing garden plants. Examples of these types of plants are fruits, vegetables, and decorative plants. Urban forestry is the science of managing trees in urban areas, whether they grow naturally in the area, or were planted ornamentally. Urban forestry is a way to improve the lives of people who live, work or spend large amounts of time in big cities. These two terms are similar in the fact they involve growth, management, humans and are considered to be a science. Ornamental gardens, gardens that produce food as well as trees in big cities all improve our lives, in giving us oxygen and creating natural beauty where we have destroyed it. The terms differ because they refer to very different subjects. Trees are very tall and need more space to grow. Trees are perennial, when most commonly garden plants are annual, with some exceptions of course.
Encyclopedia of Forest Sciences. Burley, Evans, Youngquist. Vol. 1, pg. 471
Southern Methodist University <http://environmentalprograms.net/guidance/horticulture/>
Tree Canada <http://www.treecanada.ca/programs/urbanforestry/index.htm>

Horticulture/ Tree: A tree is a large wood bodied perennial plant that has bark, a stem, and leaves. Trees are very large at maturity. Horticulture is the science of producing and taking care of these plants. Trees grow naturally in almost every climate, but with the increasing human encroachment with our cities and our cattle, the trees have taken a beating. The worldwide populations of trees are dwindeling and it is up to people like horticultursts to make sure that trees are taken care of. People in horticulture make plans to increase and protect trees, and then they cary out these plans to make sure that there are sufficient amounts of nutrients in the soil and that the trees are sufficently provided for so they can thrive. Of course horticultue is about other plants besides trees also. Liz Foster (Collins English Dictonary, Canadian edition, page 441, 442), http://www.ahs.org/, http://encarta.msn.com/dictionary_1861618832/horticulture.html
Tree Maintenance

Leaf Area Index(LAI)/Net Primary Production(NPP)
Leaf Area Index(LAI)- Leaf area per surface area of land. The ratio of leaf area to land area. "Glossary". Burns, Russel. M., Barbara H. Honkala. October 16th 2007
Net Primary Production(NPP)- Method used to record and quantify the net absorbtion of Carbon. It is an important part of measuring the carbon cycle how much carbon is taken up to produce plant growth.http://www-eosdis.ornl.gov/NPP/npp_home.html
Both of these are useful tools in measuring forest growth
Mycorrhizal Fungi / Root graft: Root Grafts are the fusing together of root systems between alike plants for support, anchorage or transfer of nutrients. Mycorrhizal Fungi is a type of fungi that grows on or around the roots of plants connecting them to one another allowing transfer of nutrients from one plant to another. So, though both share the same purpose in inter-plant transduction of nutrients, it is the method in which the nutrients are passed from one tree to the next that sets the two apart. Root Grafts transfer directly from the root of one plant to the root of another, while with Mycorrhizal fungi, it is the fungi itself act as a bridge between the two plants.

http://www.pbase.com/victorengel/image/75217392

McAbee Fossil Field/ Paleobotany: Paleobotany is the study of fossilized plants found throughout the world. These fossils provide great insight into the past and to what the world would have been like millions and millions of years ago. One such example of this is the McAbee fossil beds which are located just 13 km east of Cache Creek, They are composed of shallow lake sediments. These fossil beds have been dated to the Eocene period, about 50.2 million years ago. To date Over 50 plant species have been found here including over 40 broadleafs and 17 conifers. Of these, there are several that are no longer indigenous to the area, the sassafras and the Ginkgo trees for example. This is very important for us to know what the climate was like here in the past. There have also been many fossils of insects and fish found. The plant fossils and pollen in the sediment point to a forested landscape dominated by elm, birch and beech trees, with pines and cypress also present. Liz Foster
http://www.flmnh.ufl.edu/paleobotany/paleobotanylinks.htm: http://www.totabc.com/trellis/ecotours_outfitters/10/0/599
Fossil Cone http://www.evolvingearth.org/images/mcabeecone.jpg
Naturalized/Hybrid (Kevin Christie)
Naturalized: Of a plant or animal: having become established though not native; introduced, but growing or living and reproducing as if native.
1796 W. WITHERING Arrangem. Brit. Plants II. 336 See E. bot. 63, where it is first adopted as a naturalized plant. 1811 1st Rep. Merino Soc. 52 This kind cannot be perfectly produced but by naturalized sheep of the pure race. 1859 C. DARWIN Origin of Species iv. 115 These naturalised plants are of a highly diversified nature. 1875 Encycl. Brit. I. 84/1 A naturalised animal or plant..must be able to withstand all the vicissitudes of the seasons in its new home. 1926 W. FAWCETT & A. B. RENDLE Flora of Jamaica V. 142 Musk Ochra, Musk Seed, Wild Ochra. Naturalized and cultivated. 1960 H. S. ZIM Guide to Everglades 54 Key lime, a small, spiny naturalized citrus, is common on the Keys. 1991 Garden Jan. 21 The sedums spectabile, acre (a nasty, spreading, naturalised plant), kamtschaticum, and spurium are the common favourites. (Oxford English Dictionary Online) Hybrid: The offspring of two plants of different species, or (less strictly) varieties; a half-breed, cross-breed, or mongrel.
reciprocal hybrids, hybrids produced from the same two species A and B, where in the one case A is male and B female, in the other B is male and A female; e.g. the mule and the hinny. [1788 J. LEE Introd. Bot. (ed. 4) Gloss., Hybrida, a Bastard, a monstrous Production of two Plants of different Species.] 1828 [see a]. 1845 LINDLEY Sch. Bot. x. (1858) 167 No hybrids but such as are of a woody perennial character can be perpetuated with certainty. 1846 J. BAXTER Libr. Pract. Agric. (ed. 4) II. 358 Swedes are generally sown first. Hybrids..are usually sown next, and white turnips the last. 1867 DARWIN in Life & Lett. (1887) III. 306 The common Oxlip found everywhere..in England, is certainly a hybrid between the primrose and cowslip. (Oxford English Dictionary Online)

Paleobotany/Dendrochronology (Caitlin Deas) Both paleobotany and dendrochronology use ancient plant structures to determine past events. Paleobotany uses fossilized plants, carbon-dating them to determine when these plants lived. This information can be used to deduce what type of plants and animals lived at that time, and therefore what different things happened (such as the plant species supported a herbivore population which in turn supported a human population). Dendrochronology uses tree rings (from dead or alive trees) to determine the time that historical events occurred. Taking a core sample and analyzing it, without adversely affecting the tree, can date a living tree. Tree rings grow at a known rate, so they are a good measurement of time when compared to a structure or artifact that they are near or in. For instance, the number of tree rings added to a tree after a name is carved into the trunk tells us how long ago the name was carved. (Biology of Plants, 7th edition, Peter H. Raven, 9, 596; Cornell Tree-Ring Laboratory http://dendro.cornell.edu/whatisdendro.php)

The rings in this tree are used to determine when forest fires occurred. (SAIMA Unit of the Savonlinna Department of Teacher Education)http://sokl.joensuu.fi/saima/saimapictures/kiekkoisov.jpg

This fossil is an example of paleobotany. The plant structures shown indicate what type of species could have lived at that time.(University of California Museum of Paleontology) http://www.ucmp.berkeley.edu/IB181/VPL/Pres/PresP/Pres2.jpeg (Caitlin Deas)
Prickle and Thorn: By Conyr A. Both of these terms refer to a pointed structure found along the outer surface of a plants structure specifically the epidermis. T hey are a form of defense for the plant protecting it from possible predators by causing mild irritation or pain in its attacker. Thorns specifically are modified bracts found within the axil of the leaf or terminating the twig. Thorns are generally larger than prickles and denser. (Wikipedia thorn definition http://en.wikipedia.org/wiki/Thorn) See image:

(image from Daniel wiener webpage at http://www.danielwiener.com/daniel/tips/archives/thorns.jpg)
Prickles are defined as a sharp slender out growth on the epidermis of a plant. They can be found anywhere along the plants surface including the leaves and twigs. They consist of several layers but contain no venation. (biology online at http://www.biology-online.org/dictionary/Prickles) See image:
(image from Invasive Plants of the Eastern United States web page at http://www.invasive.org/eastern/biocontrol/23SodaApple.html)

Annual/ Biennial: In the case of annual plants the life cycle is completed in one year. The formation if flowers, fruits, and seeds rapidly decrease the food stores of the plant lead to the vegetative portion of the plants dieing. While biennial (prefix “bi” meaning two) plants takes two years (or growing seasons) to complete the life cycle where it will vegetate from a seed one year , then produces flowers and perishes the year after. Examples of some biennials are beets and carrots although they are usually harvested during the first year. Scott Horley.

Recurved and Reflexed: Both of these terms refer to leaf shape. And each of the terms include the leaf being shaped at a downward angle.
Recurved refers specifically to the leaf being curled or curved backwards or downwards.
(Biology online at http://www.biology-online.org/dictionary/Recurved)
As seen by this image:

(image from Daylilies website at http://www.daylilies.org/ahs_dictionary/recurved.jpg)

Reflexed specifically refers to the leaf having a sharp bend downwards.
(Dave’s Garden webpage at http://davesgarden.com/guides/terms/go/2086/)
As seen by this image:

(image from DK images plant section at http://www.dkimages.com/discover/Home/Plants/Classification/Tracheophyta/Magnoliophyta/Magnoliopsida/Asterales/Asteraceae-Compositae/Anthemideae/Chrysanthemum/Florists-Chrysanthemums/Fully-Reflexed/Chrysanthemum-George-Griffiths/Chrysanthemum-George-Gri-2.html)

Taxonomy and Nomenclature

§teph.L. — Thu, 29 Nov 2007 15:41:09 CST

Adaptive radiation
Alternation of generations
Anamalia
Authority
Biological species
Class
Cultivar
Derived heterotroph
Diploid
Division
Domain - Sarah Slater
Ecotype
Effective publication
Eukaryotic
Family
Fungi
Gametophyte Ryan T
Genetic isolation
Genus
Haploid
Hierarchical system
Hybrid
International Code of Botanical Nomenclature (ICBN)
Kingdom
Monotype
Morphological species - Jackie Taylor
Naturalized tree
Nomenclature
Order
Plantae - Kristie S
Priority rule
Prokaryotic
Protista - Krista Neufeld
Scientific name
Seed transfer guidelines - Andrea Chapman
Speciation
Species
Specific epithet- Kevin Christie
Sporophyte Ryan T
Subspecies
Taxon
Taxonomy
Type locality - Russ Fountain
Type specimen
Valid publication - Kirsten Jorgensen
Variety

DEFINITIONS
Please insert your definitions in alphabetical order

Adaptive radiation:The evolution from one kind of organism to several divergent forms, each specialized to fit a distinct and diverse way of life (Biology of Plants, Raven, pg. 208). Adaptive radiation typically occurs when a few organisms make their way to new, often distant areas or when environmental changes cause numerous extinctions, opening up ecological niches for the survivors (Biology, 7th Ed., Campbell Reece, pg. 480).

ex. White Spruce - Engelmen Spruce

~Quinn
Enhancement
Example: Fossil evidence indicates that mammals underwent a dramatic adaptive radiation after the mass extinctions of dinosaurs 65 million years ago. ( Biology, seventh edition, Campbell Reece, Pg 480)

This picture explains the adaptive radiation of pine cones and the adaptive radiation of the birds that eat the cones through Canada and USA ( www.uwyo.edu/benkman/Mosaic.jpg ) website, Dustie

Animalia: The kingdom Animalia is one of the 5 kingdoms and is composed of multicellular organisms with eukaryotic cells lacking cell walls, plastids, and photosynthetic pigments. Nutrition is primarily ingestive (heterotrophic). Organization and tissue differentiation is very advanced. (Raven, pg. 232) Most animals reproduce sexually, with the diploid stage usually dominating the life cycle. Contains the greatest diversity among living species. (Biology, 7th Ed., Campbell Reece, pg. 626-628) Amanda M.
(Enhancement): With a few exceptions, most notably the sponges (Phylum Porifera), animals have bodies differentiated into separate tissues. These include muscles, which are able to control locomotion by contracting, and nerve tissue, which sends and processes signals. There is also typically an internal digestive chamber, with one or two openings. (Knut Schmidt-Nielsen. Animal Physiology: Adaptation and Environment. (5th edition). Cambridge Univ. Press, 1997.)
Nearly all animals undergo some form of sexual reproduction. Adults are diploid or polyploid. They have a few specialized reproductive cells, which undergo meiosis to produce smaller motile spermatozoa or larger non-motile ova. These fuse to form zygotes, which develop into new individuals. Many animals are also capable of asexual reproduction. This may take place through parthenogenesis, where fertile eggs are produced without mating, or in some cases through fragmentation. (Klaus Nielsen. Animal Evolution: Interrelationships of the Living Phyla (2nd edition). Oxford Univ. Press, 2001.)
-Mark Dinicol

Alternation of Generations (R.Swite)
Alternation of Generations (R.Swite) A reproductive cycle in which a haploid (n) phase, the gametophyte, produce gametes, which after fusion in pairs to form a zygote, germinate, produce a diploid (2n) phase, the sporophyte. Spores produced by meiotic division, form the sporophyte give rise to new gametophytes, completing the cycle (Raven glossary)
During sexual reproduction two gametes, each of which is haploid, unite to form a single-celled zygote, which is diploid. As a consequence of the chromosome doubling that occurs during fertilization, at some point in the organism's reproductive cycle meiosis, or reductive cell division, must also occur to restore the haploid condition. In many organisms, including most animals, the zygote develops into a multicellular individual, and meiosis occurs during gamete production. In such organisms, gametes are the only haploid cells in the life cycle. In many algae and fungi, in contrast, the diploid zygote undergoes meiosis immediately to form haploid cells, called spores. Spores subsequently grow into multicellular haploid individuals. In both of these life cycles there is only one multicellular phase. In some algae and in all plants, however, there are actually two multicellular phases, one haploid and one diploid, which alternate with each other in the life cycle. http://www.bookrags.com/Alternation_of_generations.

Figure 1 Picture showing the alternation of generations
lifecycle form diploid stage to the haploid stage.
www.zo.utexas.edu/faculty/sjasper/images/29.6.gif (R.Swite)

Biological species: A species as a population or group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring, but are unable to produce viable, fertile offspring with members of other populations. (Biology, seventh edition, Campbell Reece, Pg 473) A species is a group of natural populations whose members can interbreed with one another but cannot interbreed with members of other such groups ( Biology of Plants, Raven Evert Eichhorn, Pg 207), Dustie

Enhancement The biological species concept defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance. Although appearance is helpful in identifying species, it does not define species. ExampleWestern meadowlarks (Sturnella neglecta) and Eastern meadowlarks (Sturnella magna) look almost identical to one another, yet donot interbreed with each other—thus, they are separate species according to this defintion. Nicole L. http://evolution.berkeley.edu/evosite/evo101/VA1BioSpeciesConcept.shtml)

Cultivar: A variety of plant found only under cultivation (Biology of Plants, 7th edition, Peter H. Raven, Glossary pg G-6). A cultivated variety of strain of a plant produced by horticultural techniques and not normally found in wild populations; a cultivar name is written after the Latin name, usually marked by single quotations (www.vigyanprasar.gov.in/comcom/kichammi/glossary.html). Matti
(Enhancement): A cultivar is a cultivated plant that has been selected and given a unique name because it has desirable characteristics (decorative or useful) that distinguish it from otherwise similar plants of the same species. When propagated it retains those characteristics.(http://www.hort.purddue.edu/hort/courses/HORT217/Nomenclature/description.htm).A cultivar can also be described as a particular variety of a plant species or hybrid that is being cultivated and/or is recognised as a cultivar under the ICNCP. Cultivars serve the practical needs of horticulture, agriculture, forestry, etc. (P. Gepts (2004)Who Owns Biodiversity, and How Should the Owners Be Compensated?. Plant Physiology)
-Mark Dincol

Derived Heterotroph: A derived heterotroph is an organism (in kingdon Plantea) that obtains its nutrients by feeding off another organism's nourishment. (Raven,E. and E. Biology of plants , glossary)These plants are refferd to as vascular parasites. An example of one of these plants is an Indian-pipe. The indian pipe,(Momotroap uniflora)(Brooklyn Botanical gardens(web)) which is a saprophyte obtains food from the roots of other plants via the fungal hyphae that are associated with the root system (Raven, E. and E. Biology of Plants) There are also vascular semi-parasites which are dependent to some level on a host, but can photosynthesise on their own. These are not true derived heterotrophs. (Brooklyn Botanical Gardens (web)) The name is self explanatory: Derived, meaning formed of developed from something else, and Heterotroph which is an organism that cannot manufacture its food on its own, and depends on organic substances as a food source.(Dictionary.com) By: Jake
References:
Dictionary.com (Http://dictionary.reference.com/browse/heterotroph)
Brooklyn Botanical Gardens (http://bbg/gar2/topics/botany/parts_grouping.html)
Enhancement to Derived Heterotroph (Caitlin Deas)

The Indian Pipe (Monotropa Uniflora) is a derived heterotrophy found in forests in the northern portion of North America. (Life Sciences at Brandeis) http://www.bio.brandeis.edu/fieldbio/Wildflowers_Site/IndianPipePage/Indianpipe_small0475.jpg

Diploid: Having two sets of chromosomes, the 2n (diploid) chromosome number is characteristic of the sporophyte generation
(Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-7). A cell containing two sets of chromosomes (2n), one set inherited from each parent (Biology, 7th edition, Campbell Reece, pg. 241). Matti
Enhancement: Diploid also can have two haploid nuclei in one cell (Dictionary of Natural Resource Management. p.91). Examples of diploid are zygotes (the fertilized egg cells of plant formed from fusion of male and female) of many fungi, sporophytes of symple type of eukaryotic plants, mosses, plants belonging to class and vascular plants(The concise oxford dictionary of botany. p.14,128, 235, 442). Tamiki N

Domain: (Sarah Slater) Highest and newest level of classification in the taxonomical system. Domain is one taxon above Kingdom. With new technology it is much easier to see the difference between organisms at a molecular level; therefore we are able to group them more appropriately than in the past. Every living organism will fall into one of three domains. The first two domains are Archaea and Bacteria, which have proven to be different under the microscope and live in different conditions, but they are also both single celled organisms that lack nuclei (prokaryotic). The third domain is Eukarya which includes all multi-cellular organism, these cells also contain nuclei (eukaryotic).

Biology of Plants. Raven, Evert, Eichhorn, pg. 228
University of California Museum of Paleontology <http://www.ucmp.berkeley.edu/archaea/archaea.html>

Ecotype: A locally adapted variant of an organism, differing genetically from other ecotypes (Biology of Plants, Raven, 205). A locally adapted population of a widespread species. Such populations show minor changes of morphology and/or physiology, which are related to habitat and are genetically induced. Nevertheless, they can still reproduce with other ecotypes of the same species (A dictionary of Zoology, online). -Tessa J
Enhancement: An example of an ecotype is the Lodgepole Pine (Pinus contorta) which has four varieties ranging from the Yukon down into the United States. Some of the varieties grow near sea level, and other varieties grow up in the mountains. Minimum temperatures range from 7° C (45° F) on the coast to -57° C up in the rocky mountains. As a result of this large difference in conditions, each ecotype has adapted differently.
James E. Lotan and William B. Critchfield, 2007 (http://www.na.fs.fed.us/pubs/silvics_manual/Volume_1/pinus/contorta.htm)
Jake

Effective publication refers to the method used to publish a botanical name, as necessary for it to take effect. According to the International Code of Botanical Nomenclature, the publication of a botanical name must be “by distribution of printed matter (through sale, exchange, or gift) to the general public or at least to botanical institutions with libraries accessible to botanists generally. It is not effected by communication of new names at a public meeting, by the placing of names in collections or gardens open to the public, by the issue of microfilm made from manuscripts, typescripts or other unpublished material, by publication online, or by dissemination of distributable electronic media.” Ex. 1. (A man named) Cusson announced his establishment of the genus Physospermum in a memoir read at the Société des Sciences de Montpellier in 1770, and later in 1782 or 1783 at the Société de Médecine de Paris, but its effective publication dates from 1787.(International Code of Botanical Nomenclature)
http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0033Ch4Sec1a029.htm By Caitlin Deas

Eukaryotic: cells with nuclear envelopes, complex chromosomes, and organelles, such as mitochondria, surrounded by membranes
( Biology of Plants, Raven Evert Eichhorn, Pg 4) A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. (Biology, seventh edition, Campbell Reece, Pg 8),Dustie
Enhancment:
Eukaryotic cells have a full set of membrane bound organelles. These cells make up all of the organisms in the Domain Eukarya. The Domains Bacteria, and Archaea only include prokaryotic cells. (http://www.biology-online.org/dictionary/Domain)- Nick N Enhancement (Kristie Seaborn)
The eukaryotic cells of plants are quite different from the cells of the other eukaryotic kingdom's organisms. They include the chloroplast organelle, a large central vacuole, and cell walls (can be found in a few other kingdoms).
http://www.biocrawler.com/encyclopedia/Image:Plant_cell_structure.png.

Fungi: Fungi are nonmotile, primarily terrestrial eukaryotes, which gain nutrients by absorption. They have cell walls made up of chitin, and the majority of the kingdom are multicellular, but they can also be found in the unicellular form (Biology of Plants, Raven, 230). Fungi, the kingdom of heterotrophic, single-celled, multinucleated, or multicellular organisms, live as saprobes, parasites, or symbionts, and include yeast, molds and mushrooms (The Columbia Encyclopedia, Sixth Edition, online). An example of a multicellular fungi is a mushroom and an example of a unicellular fungi is yeast. -Tessa J
Enhancement: Most fungi are composed of hyphae, which are fungal filaments. The mass of fungal hyphae that composes a fungus is called a mycelium. Hyphae grow rapidly, and an individual can grow as much as a kilometer of new hyphae within a day! (Raven, pg. 262)
Amanda Miller
Enhancement (Kristie Seaborn)Fruiting body of the scarlet cup fungus, Sarcoscypha coccinea. Hundreds of millions of meiospores (ascospores) are discharged from this cup, usually in puffs that produce visible clouds of spores.
http://www.tolweb.org/Fungi

Gametophyte: In the gametophyte phase, male and female organs develop to produce eggs and sperm, which are haploid gametes, which contain half the number of chromosomes. These gametes then fuse in fertilization. The fertilized egg called a zygote develops into the sporophyte, producing numerous single-celled spores, which in turn develop directly into new gametes. ("Alternation of Generations," Microsoft® Encarta® Online Encyclopedia 2007
http://encarta.msn.com © 1997-2007 Microsoft Corporation. All Rights Reserved.)
(Gametophyte. (2007). In Encyclopædia Britannica. Retrieved October 18, 2007, from Encyclopædia Britannica Online: http://www.britannica.com/eb/article-9365205) Ryan T
Enhancement:In bryophytes, the gametophyte is nutritionally independent from the sporophyte generation, and usually larger (Biology of Plants, Raven, pg. 236). In all plant and algae species, the gametophyte is the sexual stage of their lifecycle (Encarta Online Encyclopedia).

Genetic Isolation: Genetic isolation is the foundation of the biological species concept, which defines a species by its ability to interbreed and produce viable offspring with members of the same group. Genetic isolation states that if members of differing species could interbreed they would no longer maintain the characteristics which define them as different organisms (Biology of Plants, 7th Edition, Peter H. Raven, pg 207). Genetic isolation may be a result of geographical isolation, where species are separated by environmental conditions that prevent interaction (http://www.answers.com/topic/genetic-isolation?cat=technology). -Tori Waites

Genus: A taxonomic category found between "family" and "species" and usually containing a group of species which have the same or similar characteristics according to taxonomic criteria (Dictionary.com). The genus is used either alone or with a Latin adjective or epithet which in turn form the species half, for example, humans (Homo sapiens) belong to the genus "Homo" and the species "sapiens (Glossary terms) Dictionary.com, October 22nd 2007, http://dictionary.reference.com/browse/genus)., Glossary terms, October 22nd 2007, http://lib.store.yahoo.net/lib/allergybegone/glossary.html) StephL

Haploid- a single set of chromosomes present in the egg and pollen cells of a plant. The gametophyte of plants is the haploid stage within the alteration of generations lifecycle. A haploid gametophyte produces gametes by mitosis, which will eventually combine with a gamete of a different plant to form a zygote, hence the end of the haploid stage.(http://www.bookrags.com/Alternation_of_generations)
Mike Tomlinson

Heirarchical System: This system refers to an organization of objects linked to objects beneath it in the shape of a pyramid. The system that we would commonly think of in this context of our wikki page would be the scientific Heirarchical grouping of life. Arranged into taxanomic groups starting from the broad Domain of life (3 catagories) down through the taxanomic groups of kingdom, phylum (division), class, order,genus,species, specific epithet. (Webopedia) At the bottom of the hierarchical pyramid there is an almost infinite number of species.

References:
Carl von Linne and the Linnean System of Nomenclature (http://kheper.net/evolution/systematics/linnean.htm)
Webopedia (http://www.webopedia.com/TERM/H/Hierarchical.html)
By: Jake

Hybrid:Offspring of two parents that differ in one or more heritable characteristics; offspring of two different varieties or of two different species (Biology of Plants, Raven, pg. 209). A number of plant species are the result of hybridization and polyploidy with many plant species easily cross pollinating and producing viable seeds, the distinction between each species is often maintained by geographical isolation or differences in the flowering period (Keeton, Williams).

ex. Plantanus x acerifolia - London Plane-Tree

> The x indicates a hybrid

~Quinn
Enhancement: If sterile hybrid plants can reproduce asexually, they will become very successful. This is due to the offspring of two different species taking on the best characteristics of its parents; therefore, making it easier for the hybrid to grow in a variety of different habitats. An example of this is Kentucky bluegrass (Poa pratensis). This grass is taking over the native grasslands of the prairies. This is due to the occasional hybridization with a series of other grasses making literally hundreds of different hybrid species. (Raven. pg 214)
-Morgan Traverse

Enhancement:
An example of a hybrid is the London Plane tree. Believed to be the result of an American and Oriental Plane tree.

Leaf Fruit
http://www.english-country-garden.com/a/i/trees/london-plane-1.jpg
http://www.hort.cornell.edu/4hplants/Ornamentals/Images/London%20Plane%20Tree2.jpg
StephL

International Code of Botanical Nomenclature(ICBN)
Precise and simple system of nomenclature(naming of living things) used by botanists in all countries, dealing with the terms which rank taxonomic groups or units, and with the scientific names which are applied to the individual taxonomic(classification of living things) groups of plants. A stable method of naming taxonomic groups, avoiding and rejecting the use of names which may cause error or throw science into confusion.(http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0003Pre.htm). ICBN revolves around a set of rules which include:

The application of names of taxonomic groups is determined by means of nomenclatural types.

The nomenclature of a taxonomic group is based upon priority of publication.

Each taxonomic group with a particular circumscription, position, and rank can bear only one correct name, the earliest that is in accordance with the Rules, except in specified cases.

Scientific names of taxonomic groups are treated as Latin regardless of their derivation.

The Rules of nomenclature are retroactive unless expressly limited.(http://www.micologi.it/ICBN_main.htm)

-Danielle Dornik

Kingdom: A taxonomic category, the second broadest after domain (Biology Seventh Edition, Campbell Reece, pg. 496) one of the seven cheif taxonomic categories. (Raven, pg. G-12) Amanda M.
Enhancement: One such kingdom is the kingdom Plantae. It includes organisms that range in size from a tiny moss to a giant tree. Despite this enormous variation, all plants are multicellular and eukaryotic (i.e., each cell possesses a membrane-bound nucleus that contains the chromosomes). They generally possess pigments (chlorophylls a and b and carotenoids), which play a central role in converting the energy of sunlight into chemical energy by means of photosynthesis. ( Encyclopedia Britannica Online ) Lee Williams

Enhancement: There are 4 main Kingdoms in which we classify living, eukaryotic organisms:

- Fungi

- Protista

- Plantae

- Animalia (Raven, 231) ~Quinn

Monotype: "mono" is a prefix meaning "one" or "single". A plant or animal that is the only member of a biological group or a taxonomic category is a monotype. For example, Ginkgo has only one species, biloba and Platanaceae has only one genus, Platanus. (MSN encarta dictionary and Raven glossary (WebCT version))
Krista N
Morphological Species: (Jackie Taylor) Recognizing species based on anatomical and morphological criteria, different species look different. This concept is useful for asexual organisms, organisms that don’t sexually reproduce. Holmgren lab - http://www.biochem.northwestern.edu/holmgren/Glossary/Definitions/Def-M/morphological_species_con.html SciLinks - http://www2.una.edu/pdavis/BI%20101/evolution_is_the_core_of_modern_.htm Biology of Plants, 7th edition, Peter H. Raven, Glossary pg 207

Nomenclature: The art, process, or instance in naming something.(Merriam-Webster Online) In biological classification it's a system of naming organisms. The species to which an organism belongs is indicated by two words derived from various sources. This system, which is called the Linnaeaus System of binomial nomenclature, was established in the 1750's by Carlus Linaeus.(Encyclopedia Brittanica online) Lee Williams
Enhancement: Linnaeaus’ system of binomial nomenclature involves organizing an organism's scientific name into a combination of two terms. These terms are the genus name and the species. Both of these terms are italicized and the genus name is also capitalized (http://biology.about.com/b/a/257321.htm.)- Dennis Murengi.
Enhancement #2: Carlus Linaeus was a Swedish botanist. The first letter of the genus is not capitalized if it is being used as a common noun. If the genus and species is not italicized, it should be underlined, more commonly it is italicized. No two species can have the same specific name. Many of the genus and species names are derived from Greek or Latin origins and are descriptive of certain features. The system is used in all parts of the world and avoids the confusion caused by adoption of local names that have no meaning elsewhere. (Dictionary of Natural Resource Management, Dunster, p 36). Kirsten

Order: Order is the category of classification that is situated between class and family. Class is derived of one or more orders while order is derived of one or more families (Raven pg. G-16). The suffix for order is “ales” (Raven, pg. 221). Order is the fourth level in the classification system and was created by Carl Linnaues (AndersBacklund, http://www.systbot.uu.se/information/history/linnaeus.htm) -- John
Pinnate: Of a compound leaf: composed of a series of (usually opposite) leaflets arranged on each side of a common petiole; (of a fern frond) composed of a series of pinnae; (a primary division, or leaflet, of a compound leaf) arranged on each side of the rachis (main axis from which the pinnae arise). Also: (of leaf venation) consisting of a series of lateral branches arising on each side of the midrib. Cf. BIPINNATE adj., TRIPINNATE adj.
alternately, odd-, oppositely pinnate, etc.: see the first element. Juglans nigra (Black walnut) leaf, a Pinnately compound leaf structure.

Plantae (Kristie Seaborn) Multicellular eukaryotes that make organic molecules by photosynthesis (Biol. Concepts and Connections 4th ed., Pg. 346). The photosynthetic nutrition, in which chemical energy is produced from water, minerals, and carbon dioxide with the aid of pigments and the radiant energy of the Sun.They have essentially unlimited growth at meristems.They have cells that contain cellulose and are therefore to some extent rigid (Encyclopedia Britannica Online).

Enhancement: Plants are autotrophic, have cells walls, and are terrestrial organisms which means they primarily live on land. As well, they have an alternation or generations, going between sphorophyte and gametophyte generations, sporophyte being the dominant phase. Lastly, plants either repoduce through spores or seeds (Raven, 233-236) ~Quinn

Priority Rule- According to the ICBN, the oldest valid published name of a plant or a species is the one that gets used. This is true except in some cases where it is decided that a new name would "disturb stability or universality or cause confusion," then it would be decided that he other name would stay. An example of a name change because of the priority rule is: the Pseudotsuga menziesii, Douglas fir. It was for many years called by another name, but someone was doing research and found a reference to the tree that had been validly published by Archibald Menzies, the ships surgeon with Captain Vancouver in the 1700’s. Because of the priority rule, the name that Menzies had originally created took the place of the name at the time. http://home.earthlink.net/~misaak/taxonomy.html (Earthlink); http://www.lewis-clark.org/content/content-article.asp?ArticleID=1509 (Lewis and Clark)
Liz Foster

Prokaryotic: A type of cell without a membrane enclosed nucleus or membrane enclosed organelles (Biology of Plants seventh edition Pg. 37). Prokaryotic cells are smaller than eukaryotic cell. Examples of a prokaryotic cell are: bacteria and archaea. (Biology, seventh edition, Cambell Reece, pg 8). Nick N Enhancement
This picture is a prokaryotic cell, Just by telling that there is a lack of true nucleus and there is no membrane-enclosed organelles making the cell simple compared to a eukaryotic cell. ( http://www.daviddarling.info/images/prokaryotic_cell.jpg ) Dustie
Enhancement: Cells that lack a membrane-bound nucleus are called prokaryotes (from the Greek meaning before nuclei). These cells have few internal structures that are distinguishable under a microscope. Cells in the monera kingdom such as bacteria and cyanobacteria (also known as blue-green algae) are prokaryotes. http://library.thinkquest.org/C004535/prokaryotic_cells.html (R.Swite)
Enhancement
The prokaryotic cell is beleived to be one of the origins of life. Examples of this include the eukaryotic organelles, the mitochondria and the chloroplast. The chloroplast was believed to originate from cyanobacteria. Evidence of this is demonstrated by the chloroplasts multiple membrane systems and having tis own DNA which lead to the believe that a endosymbiosis event has occured in which a eukaryote has acutally engulfed the chloroplast earlier in the process of evolution. The mitochondrion also has its own independent genome. This DNA shows similarity to bacterial genomes, and, fives evidence again to the endosymbiosis theory.Henze K, Martin W (2003). "Evolutionary biology: essence of mitochondria". Nature 426 (6963): 127-8. Martin W, Rujan T, Richly E, Hansen A, Cornelson S, Lins T, Leister D, Stoebe B, Hasegawa M, Penny D (2002). "Evolutionary analysis of Arabidopsis, cyanobacterial, and chloroplast genomes reveals plastid phylogeny and thousands of cyanobacterial genes in the nucleus". Proc Natl Acad Sci 99:
Mike Tomlinson

Protista - These are eukaryotic one-celled living organisms, without highly specialized tissues, distinct from multicellular plants and animals. They include protozoa (animal-like protists), slime molds (fungus-like protists), and eukaryotic algae (plant-like protists). The word protist means "the first of all ones" and are said to be paraphyletic. The kingdom protista is comprised of eukaryotic organisms (they belong to the domain eukarya) that do not fit into any other kingdom.

(http://en.wikipedia.org/wiki/Protista) (http://www.ask.com/reference/dictionary/wordnet/130824/Protista) Image references (Left to Right) (http://www.microscopy.fsu.edu/primer/techniques/hoffmangallery/images/stentor.jpg) (http://www.nearctica.com/biomes/edf/mushroom/mush10.jpg) (http://www.wiu.edu/users/mfkck/micr200/nostoc.gif) Krista Neufeld

Scientific name (DennisMurengi) – The Latin name of an organism used to rank an organisms species, genus or family according to internationally agreed rules. http://www.practicalfishkeeping.co.uk/pfk/pages/glossary.php?entry_name=Scientific+name
This system of naming is called binomial nomenclature (the American heritage dictionaries). Scientific names are used for some of the following reasons: they help prevent confusion of many common names over different nationalities, they allow exact identification of an organism, and scientific names are unique. Examples: Quercus rubra L. (Trees in Canada pg.248), Populus balsamifera L. (Trees in Canada pg.340).

Seed Transfer Guidelines (Andrea Chapman) – Guidelines set out by government in order to regulate where specific species are planted within the province (Yanchuk 2007). Guidelines change depending on the governing body (example, can be different in the USA than in Canada) and ensure the climatic conditions are adequate for the species planted to avoid maladaptation. Maladaptation occurs when species that become accustomed to their climate range are moved to a foreign climate reacting by means of slow growth, cold injury, stem defects, etc. (O’Neill and Yanchuck 2005).

Yanchuck A. 2007. Climate change and seed transfer. Government of British Columbia. URL http://www.for.gov.bc.ca/hre/forgen/seedtransfer/seedtransfer.htm
O’Neill G. and Yanchuck A. 2005. A primer on seed transfer for compliance and enforcement in B.C. Government of British Columbia. URL http://www.for.gov.bc.ca/hre/forgen/seedtransfer/SeedTransferPrimer20.pdf

Speciation: This is the origin of new species in evolution; the evolutionary formation of new biological species, usually by one species that divides into two or more species that are genetically unique. (MSN encarta dictionary and Raven glossary(WebCT version))
Krista N
Enhancement: Speciation is the divergence of one species, primarily thought to be the result of geographical isolation. Geographical isolation combined with very different environmental factors is thought to be the raw material of speciation. The random change of alleles of the isolated groups is genetic drift. If these populations are apart for long enough they may become so different that they may not reproduce with their original species. The second idea is that speciation may be the result of adaptive radiation, where individuals with physical or behavioral traits may only interbreed with one another, causing a change in allele frequency, resulting in speciation.
Reference: American Heritage Science Dictionary, 2007, (http://dictionary.reference.com/browse/Speciation)
Enhancement #2:
Speciation is a lineage-splitting event that produces two or more separate species. Something happens so that a single species is divided, something like a hurricane blowing some flies to another area. These two different groups mate and produce offspring and following the theory of adaptive radiation, only the strong survive. These stronger offspring then mate together and on it goes. After a long time these species have evolved into a whole new species or subspecies, to better suit it’s environment.
Liz Foster
Enhancement #3:

An experiment demonstrating allopatric speciation in the fruit fly (Drosophila pseudoobscura) conducted by Diane Dodd. A single population of flies was divided into two, with one of the populations fed with starch-based food and the other with maltose-based food. After the populations had diverged over many generations, the groups were again mixed; it was observed that the flies continued to prefer mating with others from the same original population.
Edited in Inkscape by User:Fastfission based on versions by User:BenB4 (Image:Speciation experiment.svg) from Ilmari Karonen's Image:Drosophila speciation.svg, based on http://evolution.berkeley.edu/evolibrary/images/evo/drosophila_experiment.gif from http://evolution.berkeley.edu/evolibrary/article/0_0_0/evo_45
Kevin C.

Species: (Mallory Hazell) In Latin, species simply means "kind," and so species are, in the simplest sense, different kinds of organisms. By one diffinition, a species is a group of natural populations whose members can interbreed with one another but cannot (or at least usually do not) interbreed with members of other such groups. (Biology of Plants. Raven. pg. 207)

Enhancement: (Sarah Slater) Species can be classified by the biological species concept or more commonly in plants the morphological species concept. Biological species concept is mentioned above: populations being able to interbreed only within that population. Morphological species concept is based on anatomical features and DNA. This is mainly used for plants, as hybrids are common. The name given to species is considered a binomial name, or two part name and also in latin. It consists of a genus name, which is the genus in which the species is apart of, and the scientific epithet or a more specific name.
Biology of Plants. Raven. G-22
The Chicago Botanic Garden <http://www.bestplants.org/glossary.htm>

Specific Epithet: Of or pertaining to, connected with, etc., a distinct species of animals or plants. specific epithet (chiefly Bot. and Microbiology), the second (adjectival) element in the Latin name of a species according to the binomial system, which follows the generic name and serves to distinguish a species from others in the same genus; specific name, (a) (now chiefly Zool.) = specific epithet above; (b) (now chiefly Bot. and Microbiol.), the Latin name of a species, which in the binomial system comprises a generic name and a specific epithet.(Oxford English Dictionary Online)The second part of a species name; for example, mays of Zea mays, which is maize.(Raven, p. G-22). Kevin C

Sporophyte: A multicellular diploid resulting from the union of gametes produced by Gametophytes. These diploid cells divide using meiosis, into haploid cells called spores which in turn regenerate Gametophytes through mitosis. (Biology, seventh edition, Campbell Reece, pg 242) Each phase Gametophyte and Sporophyte,creates the other. (sporophyte. (2007). In Encyclopædia Britannica. Retrieved October 18, 2007, from Encyclopædia Britannica Online: http://www.britannica.com/eb/article-9069221 ) Ryan T
Enhancement: In trees and other vascular plants, the sporophyte is the larger and more structurally complex generation (Biology of Plants, Raven, pg. 376). A key characteristic of the sporophyte generation is that its reproductive cells or spores are asexual; each spore germinates to produce a gametophyte (Encarta Online Encyclopedia). Tessa J
Enhancement- The following picture clearly labels the sporophyte generation -- John

Subspecies: The main taxonomic subdivision of a species. (Biology of Plants seventh edition Pg 221) It is a taxonomic group that is less distinct from the species it originates from. The species will evolve and change because of climate or habitat change when it is isolated from the original species, causing a subspecies to emerge. ( http://www.biology-online.org/dictionary/Subspecies)- Nick N
Enhancement: A subspecies is also refered to as a "variety". All members of a subspecies or variety of a given species resemble each other and share one or more features not present in other subspecies or varieties of that species. (Raven, pg. 221)
Amanda M
Enhancement
A subdivision of a species: as a category in biological classification that ranks immediately below a species and designates a population of a particular geographic region genetically distinguishable from other such populations of the same species and capable of interbreeding successfully with them where its range overlaps theirs. ( Merriam-Webster’s Collegiate dictionary- Seventh ed.) Dustie

Taxon: (plural taxa) or Taxonomic Unit is a group or category at any level of the classification system of plants or animals. These taxa are pertaining to the groupings used in the classification of organizations. Taxonomic categories are:Kingdom, Phylum, Class, Order, Family, Genus and Species. The taxon of something is essentialy it's rank. Liz Foster http://www.m-w.com/cgi-bin/dictionary?taxon (Merriam and Webster)

Taxonomy: Taxonomy is derived from Greek word Taxis "arrangement" and nomos "law" ( Botanica online Encyclopedia). Therefore, it is a science of identifying, naming, and classifying of organism species (Biology of plants, seventh edition, Raven, 219) in hierarchial system. This system includes Kingdom (Plantae), Division (Tracheophyte), Class (Anthrophyta), Order (Fagales), Family (Betulacese), Genus (Betula), and Specific epithet (papyrifera) (Forest Ecology and Botany, Rhys, B-10). Tamiki N
Enhancement (Ryan T) "Taxonomy is the method by which scientists, conservationists, and naturalists classify and organize the vast diversity of living things on this planet in an effort to understand the evolutionary relationships between them." Jamie Fenneman: E-Flora BC (Retrieved Nov 28, 2007) from http://www.geog.ubc.ca/~brian/florae/IntroductiontoPlantTaxonomy.html

Type Locality (Russ Fountain)
The type locality of a species is the geographical place of collection of the specimen. (International Code of Zoological Nomenclature - http://www.iczn.org/iczn/index.jsp?nfv=&article=76) If new species is discovered, one specimen will be taken from it’s natural habitat to represent the entire species, and the exact location from which that specimen was taken is called the type locality. If the name-bearing type was captured or collected after being transported by boat, vehicle, aircraft, or other human or mechanical means, the type locality is the place from which it began its unnatural journey. (http://filaman.uni-kiel.de/LarvalBase/Glossary/Glossary.cfm)

Type Specimen: A single member of a species that is used to represent all members of that species(http://www.biology-online.org/dictionary/Type_series). This specimen is usually used as a basis for comparison to determine if other specimens are members of the same species or not. (Raven pg 221) – Morgan Traverse
Enhancement (Sarah Slater): A type specimen is a real plant taken from a natural environment that is kept safely in a herbarium to refer to at any point. It is the original plant that was used to name and classify the species. The plant must be a good representation of the species as it will be kept forever to compare other specimens to. In the past drawings may have been used as type specimens, as technology was not as advanced and preserving real plants was not commonly practiced. Written by Jim Foley of Talk Origins <http://www.talkorigins.org/faqs/homs/typespec.html>
National Herbarium of New South Wales <http://plantnet.rbgsyd.nsw.gov.au/HerbLink/NSWtypes/type.html>

Variety: When specific kinds of organisms do not fit exactly into a species, but are still members of that species, they are put into a group that is less than species rank.These species names are ternary, in that they have three parts. This can sometimes be viewed as the same as a subspecies, or divisions of subspecies. An example is lodgepole pine. It is Pinus contorta var. contorta. (http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0008Ch1Art004.htm)
- Morgan Traverse

Enhancement (Kristie Seaborn) Another good example of a variety is Acer glabrum var. douglasii (Douglas maple). It is a shrubby western tree found in B.C. along streams and on moist sites. ( Trees in Canada pg, 150)

(http://www.cas.vanderbilt.edu/bioimages/species/acgld4.htm )

Naturalized tree: A woody perennial plant ( http://www.britannica.com/dictionary ) originating in another region that becomes established in a new environment, or adapts successfully to new environmental conditions.(Encarta Dictionary Online) An example of a naturalized tree to North America is the London Plane Tree (Platanus x acerifolia) The London Plane tree is a hybrid of the American and Oriental Plane tree and is particularly well adapted to urban conditions. (http://www.yardener.com/LondonPlaneTree.html, Yardener’s Advisor Newsletter online)
- Nicole H. Enhancement: Another example of a naturalized tree is the Russian olive (Elaeagnus angustifolia). This tree is native to Europe and western Asia. It is also used extensively in the prairies to provide windbreaks. (Plants of Southern Interior British Columbia and the Pacific Northwest. Parish et. al. pg 71) - Morgan Traverse
Enhancement: (Mallory Hazell) A naturalized tree is an introduced species (a species of tree that has been introduced into a different region) that escapes cultivation and grows freely. In other words it becomes common and established as wild. It behaves like a native species, which grow naturally and spontaneously in undisturbed forest.

The London Plane is a hybrid between the Oriental Plane (P. orientalis) and the Western or American Plane (P.occidentalis). This tree pictured here is an example of a naturalized tree.
(www.the-tree.org.uk/.../TreeGallery/Plane.jpeg) Matti Harper
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Valid PublicationA method of publication that adheres to the International Code of Botanical Nomenclature. The rules aim to create a precise and simple system of nomenclature that can be used internationally. This supplies means of referring to it and indicate its taxonomic rank, without confusion. The publication must be valid and all components of the description must be included in the publication. These rules are decided by the Sixteenth International Botanical Congress. Kirsten Jorgensen(International Code of Botanical Nomenclature: http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0001ICSLContents.htm Retrieved November 29, 2007)(International Journal of Systematic and Evolutionary Microbiology http://ijs.sgmjournals.org/cgi/content/full/56/11/2715, Retrieved November 29, 2007.)

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COMPARE AND CONTRAST
Please put your compare and contrast entries below here

Adaptive radiation/Hybrid: Adaptive radiation is the differentiation of a species through evolution. It is the process of one species evolving into many different species with different morphological and physiological traits, in a variety of environments (Shluter 2000). A hybrid is a viable offspring that is produced between two genetically different species (Oxford Dictionary). Hybridization is the process of producing a hybrid by breeding between two genetically different strains, populations, or species (Dunster J. 1996). Adaptive radiation and hybridization are similar because the offspring produced are genetically different then their ancestors. However, the process leading up to these changes is much different. In adaptive radiation, the process occurs within a rapidly multiplying lineage influencing the entire population (Shluter 2000), where in Hybridization, it occurs to an individual. Adaptive radiation is said to occur primarily due to the population exploiting different resources (Shluter 1995). Hybridization is an event where two different species under the same genus happen to interbreed, making it more of a chance event, not a process of evolution as is true with adaptive radiation. Andrea Chapman

Dunster J. 1996. Dictionary of natural resource management. UBC Press. Pg 166
Oxford English Dictionary Online http://dictionary.oed.com.ezproxy.tru.ca/cgi/entry/50109750?single=1&query_type=word&queryword=Hybrid&first=1&max_to_show=10
Schluter D. 2000. The ecology of adaptive radiation. Oxford University Press. pg 10 URL http://books.google.ca/books?hl=en&lr=&id=Q1wxNmLAL10C&oi=fnd&pg=PP8&dq=Adaptive+Radiation&ots=4nP1SFaNxu&sig=3VtfyXyEao7XfVOPmcKOmGolMGQ#PPA286,M1

Schluter D. 1995. Adaptive radiation in sticklebacks: trade-offs in feeding performance and growth Ecology 76 (1): 82-90 URL http://www.jstor.org/view/00129658/di960364/96p0065p/0

Adaptive Radiation/Speciation: Speciation refers to the origin of species - specifically: allopatric speciation, which refers to speciation that occurs through the geographic separation of species, and sympatric speciation and occurs without geographic isolation (Biology of Plants, 7th Edition, Peter H. Raven, pg 209). Adaptive radiation involves the rapid adaptation of one species into several in order to exploit specific niches. An example of adaptive radiation would be “Darwin’s Finches” – specifically the variation of the beaks of finches habituated on the Galapagos Islands (http://www.pbs.org/wgbh/evolution/library/01/6/l_016_02.html). - Tori Waites

Genetic Isolation/Adaptive radiation: (Mallory Hazell) Adaptive radiation is the evolution from one kind of organism to several divergent forms, each specialized to fit a distinct and diverse way of life. Genetic Isolation is an event that separates a species of trees over a long period of time until the new regions of trees become so different they can no longer interbreed. Therefore, genetic isolation is a form of adaptive radiation in trees. The evolution of one species of tree into several different forms of that tree each specialized to a different region. (Biology of Plants. Raven. Pg. G-1)

Angiosperm/Gymnosperm: A angiosperm is any of a class (Angiospermae) or division (Magnoliophyta) of vascular plants (as magnolias, grasses, oaks, roses, and daisies) that have the ovules and seeds enclosed in an ovary, form the embryo and endosperm by double fertilization, and typically have each flower surrounded by a perianth composed of two sets of floral envelopes comprising the calyx and corolla —called also flowering plant (Merriam-Webster Online)
Gymnosperms, the other large group of vascular seed plants, do not develop seeds enclosed within an ovary but are
usually borne exposed on the surfaces of reproductive structures, such as cones, that originally produced the spores. any vascular plant that reproduces by means of an exposed seed, or ovule, as opposed to an angiosperm, or flowering plant, whose seeds are enclosed by mature ovaries, or fruits.The seeds of many gymnosperms (literally, “naked seed”) are borne in cones and are not visible. These cones, however, are not the same as fruits. During pollination, the immature male gametes, or pollen grains, sift among the cone scales and land directly on the ovules, which contain the immature female gametes, rather than on elements of a flower (the stigma and carpel) as in angiosperms. Furthermore, at maturity, the cone expands to reveal the naked seeds. (Encyclopedia Britannica Online ) Lee Williams.

Gymnosperm Cone and Angiosperm Flower

Passion Flower By magzie on Flickr

www.flickr.com/photos/magzie/823542168/ Cone found on: midkit.100megsfree5.com/stateflowers.html Lee Williams

Cultivar/Subspecies: (AarenS)

A cultivar is a race or variety of plant that has been created and maintained through cultivation for traits that are found to be desirable (decorative or useful).
(http://www.hcs.ohio-state.edu/hcs/TMI/HORT234/Nomenclature.html)
(http://www.biology-online.org/dictionary/Cultivar)
A subspecies is when a species of tree becomes acclimated to a certain area and the following generations become more and more specialized to live in that one area.
(http://www.answers.com/topic/subspecies)
(Biology of Plants, 7th edition (pp g-23)
Subspecies and cultivar are similar in that they are both genetically specialized to serve a purpose and have been very selectively bred to succeed at doing this. They differ in that a subspecies is a naturally occurring phenomenon, and cultivars occur due to direct human intervention.

Cultivar and Ecotype: Both terms refer to a plant species that has been changed or grown/grows in an unusual location that it would not naturally be found in. However, the cultivar has been planted by people to grow in said location and the tree may or may not adapt to the new environment. The cultivated species is also genetically alike to the original strain unlike the ecotype. The ecotype is a naturally occurring genetic variation of a plant species in which it has adapted to the local environment. Ecotypes are not genetically similar to other members or its genus separating them. (Biology of Plants, 7th edition, Peter H. Raven, G-8,G-6 and The free dictionary by Farlex at http://www.thefreedictionary.com/ecotype)
By Conyr Aird

Biological species concept vs. Morphological species concept. (Katherine Loewen)

The biological species concept defines a species based on genetic isolation from other groups of organisms. It suggests that a species can be defined by an inability or lack of inclination to mate with other groups thus maintaining a consistent genetic makeup of a population. This definition of a species does not always apply in nature as species can and do interbreed to produce fertile hybrids on a regular basis. (Raven 6th ed.)

The morphological species concept defines a species based on similarites and differences in appearance. It is the most practical and widely used method of differentiating species (Etelka, 2006)

The biological and morphological species concepts use different ideas to decide whether an organism belongs to one species or another. The biological species concept does not take into account the appearance of an organism when defining species, only what other organisms it can interbreed with. On the other hand, the morphological species concept will define a group of organims as a single species even if it can interbreed with a different kind or kinds of organisms.

Derived Heterotroph/Heterotroph: An heterotroph is an organism that cannot manufacture organic compounds and so must feed on organic materials that have originated in other plants and animals. (Biology and Plants 6th edition, Pg. G-18 The vast majority of heterotrophic organisms evolved from other hetertrophic organisms. The exception of this tendency is the derived heterotroph, which is an organism that evolved from an autotroph that can manufacture organic material without the consumption oranisms, into an organism that is required to gain nutrients from an organism. An example would be Monotropa uniflora (Indian Pipe) which is white due to the fact that no photosynthetic pigments are present in the plant's tissue. Indian Pipe is evolved from the blueberry family and is technically a flowering plant, however it rely entirely on the nutrients of mycorrhizal fungi which are symbiotic with autotrophic plants. Other herotrophic plant depend on plants for nutrients or in extreme cases, such as the Venus Flytrap (Dionaea muscipula), animals.(http://botit.botany.wisc.edu/toms_fungi/oct2002.html) Robin Anders

Domain/Kingdom: Domains and Kingdoms are both catagories of taxinomic groupings(http://101science.com/Taxonomy.htm) A Domain is the highest of all the taxonomic groupings, in it are the 3 domains: Archaea, Bacteria, Eukarya. A Kingdom is just below Domain in the taxonomic catagories: The Kingdoms are Monera, Protista, Anamalia, Plantae, and Fungi (Glossary: Biology of Plants) VanessaV
Domain/ Division:There are three domains of living organisms: Bacteria, Archaea, and Eukayra. Domains are the highest grouping of all organisms. Divisions are a taxinomic category to designate groupsof the plant kingdom. (Biology of Plants, 7th edition) Travis Unsworth

Drupe/ Pom: A drupe is a one-seeded indehiscent fruit having a hard bony endocarp, a fleshy mesocarp, and a thin exocarp that is flexible (as in the cherry) or dry and almost leathery (as in the almond). (Merriam-Webster Online)

A fruit in which the outer layer of the ovary wall is a thin skin, the middle layer is thick and usually fleshy (though sometimes tough, as in the almond, or fibrous, as in the coconut), and the inner layer, known as the pit, or putamen, is hard and stony. Within the pit is usually one seed, or, rarely, two or three, in which case only one develops fully. In aggregate fruits such as the raspberry and blackberry—which are not true berries—many small drupes are clumped together. Other representative drupes are the cherry, peach, mango, olive, walnut, and dogwood. (Encyclopedia Britannica Online) Lee Williams

Pomes are multiple fleshy fruits of the rose family (Rosaceae) in which an adnate hypanthium becomes fleshy (apples and pears).(Encyclopedia Britannica Online) A fleshy fruit consisting of an outer thickened fleshy layer and a central core with usually five seeds enclosed in a capsule. Ovary or core surrounded by edible, fleshy receptacle tissue (hypanthium or fleshy floral tube) that is really not part of the pericarp. The actual ovary or core is usually not eaten, at least by most humans. This is typical fruit of certain members of the rose family (Rosaceae), including apple, pear, quince and loquat. (Merriam-Webster Online) Lee Williams

Pome image: waynesword.palomar.edu/images/pome1.jpg
Drupe Image: www.botany.hawaii.edu
Lee Williams

Gametophyte/ Sporophyte: In plants that have an alternation of generations, the gametophyte is the haploid (n), gamete-producing generation, and the sporophyte is the diploid (2n), spore-producing generation. In trees, and other vascular plants, the sporophyte is the larger and more structurally complex generation, whereas the gametophyte is a step in the life cycle of the plant, and production of the sporophyte. In bryophytes, on the other hand, the gametophyte is the larger and more dominant generation, but can still be considered a “step” in its life cycle. The sporophyte produces haploid spores, which eventually produce gametophytes. The gametophyte then produces eggs or sperm, which after fertilization will become the sporophyte. (Biology of Plants, Raven, 236, 376). In plants with alternating generations, the gametophyte is the gamete-producing and usually haploid phase, producing the zygote from which the sporophyte arises. It is the dominant form in bryophytes. The sporophyte is the asexual, and usually diploid stage, producing spores from which the gametophyte arises. It is the dominant form in vascular plants (The Oxford Pocket Dictionary of Current English, online). –Tessa J

Genetic isolation/ ecotype (Sarah Slater): Genetic isolation is the process of species expanding to live in a greater geographical range. When large geographical range has been covered, species are often separated into different ecosystems. During this process species must adapt to the new environment in which they live. An ecotype is a subset of a species that has adapted to its environment in a way that makes the population genetically different from members of the same species. Therefore, an ecotype is the result of genetic isolation.

These two terms coexist with one another, and are therefore similar. They are both terms that refer to the environment in which a species lives. These two terms are also different as genetic isolation is a process, and an ecotype is a result of this process.

Biology of Plants. Raven, Evert, Eichhorn. Pg. 205
Dictionary of Biology. Thain, Hickma. Pg. 175
Genus/ Species: Taxonomic categories, They are the two lowest ranks of taxonomic categories. Species are different types of organisms while genus is the second name of the species which identifies more specifically. An example of this is Pinus ponderosa and Pinus contorta . The Pinus is the species and the genus is the second word. (Biology of Plants, 7th Ed.) Travis Unsworth

Haploid/ Diploid: Haploid refers to a single set of chromosomes, and is written as n. Diploid refers to having a double set of chromosomes, and is written as 2n. In a trees lifecycle, the spores and gametes have haploid status, and the somatic cells, or the sporophyte generation, has diploid status (Biology of Plants, Raven, pg.41). Haploid is having half of the diploid or full complement of chromosomes, that is, one complete set, as in mature gametes, whereas diploid is having two complete chromosome pairs in a nucleus (2N) (McGraw-Hill Access Science, Encyclopedia of Science & Technology Online). The haploid stage occurs after meiosis, and the diploid stage occurs after mitosis. -Tessa J

Hybrid/Cultivar A hybrid is and organism of two parents that differ in one of more heritable characteristics, especially the offspring of parents of different varieties or species. A hybrid may quite often display Hybrid Vigor which is having measurably better characteristics than both of its parents. Hybrids are commonly sterile. In contrast, a cultivar is a plant that has been created or selected intentionally because of its traits by humans and has maintained its uniquiness by human cultivation. A Cultivar may be a hybrid or it may not.( American Heritage Science Dictionary) A cultivated species is a plant found only under human cultivation. (Raven et al, Biology of plants, pg. g-7) An example of a Cultivar is the Lombardi Poplar ( Populus nigra italica) which was hybridized for its upward pointed branches and fast growth.( Crystal Reference Encyclopedia) Hybrids are sometimes found in the wild, a cultivar is a not, unless it is planted there by humans. An example of a hybrid is a Platanus x acerifolia The London Plane Tree which is a fully fertile hybrid.(Encyclopedia Britanica Online) It could be argued that this tree would not have come to be without human cultivation, but there is other hybrids that occur in the wild. A cultivar is plant species that has been selectively bred by humans.
Ref: American Heritage Science Dictionary. 2007 (http://dictionary.reference.com/browse/hybrid)

Encyclopedia Britannica Online. 2007 (http://www.britanicca.com/article/londonplane)

Crystal Reference Encyclopedia (http://www.reference.com/search?q=lombardy%20poplar)

Introduced tree/Naturalized tree (AarenS) A naturalized tree is an introduced species that has become common and established itself as though wild, reproducing naturally and spreading. (http://www.americanforests.org/resources/bigtrees/faq.php) An introduced tree is a tree brought from a different area and grows, but does not reproduce or spread as a population in its habitat. (Biology of Plants, 7th edition) A naturalized tree and a introduced tree are similar in that they are both brought in to a habitat where they are not considered part of the native species. They differ because a naturalized tree can reproduce and increase in population, whereas an introduced tree will not reproduce or expand into other areas.

Kingdom/Division: Kingdom is the taxonomic category which has five parts, Plantae, Fungi, Animalia, Protista. (Biology seventh edition Pg. 497) Kingdom, is below the group Domain and above the group Division. The Division known as also known as the phylum, each kingdom (ex. animalia, plantae) has many phylums with in it. The division is a smaller group than a kingdom but there are more of them. The division is above the group Class.(Biology of Plants seventh edition Pg. 221) –Nick N

Plantae/Animalia: These two kingdoms both consist of multicellular eukaryotes, but members of the kingdom Plantae are autotrophic and members of the kingdom Animalia are heterotrophic (Capmbell Reece, 7th Ed.). Plants are always stationary and are able obtain energy in one spot, while animals are motile and must move in order to find food. Aswell, most plants are terrestrial (trees, grasses) and most animals are aquatic (whales) (The Canadian Encyclopedia).

On a cellular level: Plants: cell wall, chloroplasts, large central vacuole

Animals: no cell wall, no chloroplasts, no large central vacuole ~Quinn

Enhancement

This picture represents the kingdoms. Here we have the Plantae, animlia and fungi having the same cells. This represents the similarities of plantae and animalia. NOT THE DIFFRENCES (http://www.emc.maricopa.edu/faculty/farabee/BIOBK/kingdoms.gif ) Dustie

Morphological/ Biological Species Concept:Morphological species are recognized by their anatomical (structural) criteria and the fact that they can interbreed with other species to produce fertile offspring. Biological species are recognized primarily by genetics and the fact that they cannot interbreed with other species – gentic isolation (Raven, pg. 207). For example, humans are capable of interbreeding, but they are separate and cannot interbreed with chimpanzees – so they remain different species, where as trees can (Campbell Reece, 7th Ed). Plants are identified primarily under the morphological species concept since it would be very difficult to follow their gene flow. ~Quinn

Order/Family Order is a category of classification between the rank of class and family; classes contain one or more orders, and orders in turn are composed of one of more families. (Biology of Plants, 7th edition, Raven, Pg G-16) Family is a taxonomic group between order and genus in rank; the ending of a family names in animals and heterotrophic protistas is –idea; in and all other organisms is –aceae. A family contains one or more genera, and each family belongs to an order. (Biology of Plants, 7th edition, Raven, Pg G-8) Order and Family are both apart of the binomial nomenclature, the process of grouping and assigning names to individual things. Nicole L

Kingdon fungi/Kindgom Plantae:
Kindgom Fungi includes Eurkaryotic multicellular absorbers(thought there are very few unicellular fungi, e.g Yeast). Memebers of this kindgom are non-motile that lack photosynthetic organs and plastids.Can reproduce sexually or asexually. They absorb their nutrients using powerful enzymes which break down materials into nurtients for the fungi from organisms that may be dead or living. This kingdom used to be lumped in with the kingdom plantae but with new technology the comparison of rRNA sequences indicates fungi are more closely related to animals then they are to plants. Kingdom Plantae includes Eukaryotic multicellular photosynthesizers. Plant cells contain vacuoles and have cell walls made of cellulose. The main way of getting nutrition for a plant is Photosynthesizing, though few plants have become heterotrophic. Reproduction is primarily sexual with cycles of alternating haploid/diploid generations (Biology of Plants P. 231-233)
Some similarities between the two kingdoms are they both contain Eukaryotic cells, and it is very common for plants and fungi to work together in a symbiotic relashionship. Lots of string like fungi in a plants roots pass on nutrients from the plant to the fungi, and from the fungi to the plant. (http://www.naturegrid.org.uk/biodiversity/crypfungi.html#import) VanessaV

Scientific Name vs Scientific epithet: A scientific name is the latin name given to an organism used in taxomony. It is a universal two-part scientific name consisting of a genus and species. This system of naming is also refered to as binomial nomenclature. Scientific names are established using a standard set of international rules. All scientific names are published in a location open for pubic review. The importance of this naming system is that it allows all individuals throughout the world to recognize a species. and have full access for critical review. Each scientific name is unique, often using descriptive terms to give insight into species behavior and/or preferred habitat and location. It is written underlined or italized.

The species name is found following the genus in a scientific name. The species is also referred to as the scientific epithet. Therefore, the scientific epithet is the second part of the two-part taxonomic naming system. It is a latin noun or adjective applied to describe an actual or attributed quality.

References:

University of Michigan Museum of Zoology Animal Diversity Website (http://animaldiversity.ummz.umich.edu)
Merriam- Webster Online (http://www.m-w.com/dictionary)

-Nicole H.

Species/Subspecies: (Mallory Hazell) A species is the original organism that is able to interbreed with members of its own kind. Where as a subspecies is a variation of the original species that can no longer breed with members of its own kind. This is due to events such as genetic isolation, where a population of species is isolated from another population of the same species and over time become so different they can no longer interbreed. The original species and its subspecies usually share common features. However, all the members of a subspecies will have shared traits not present in other subspecies of the original species. (Biology of Plants. Raven. pg. 207.)

Species/Subspecies: A species is a group whose members possess similar anatomical characteristics and have the ability to interbreed, and have the same binomial name. (Campbell Reece, 7th Edition) Whereas a subspecies, sometimes called variety, is the taxonomic division of a species. (Raven, G-22) An organism that is classified as a subspecies of a species has a three part name, the first two words are the species name, and the third is the subspecies, or variety. For example, the peach tree is Prunus persica var. persica, but the nectarine is Prunus persica var. nectarina. (Raven, pg. 221) An organism classified as a subspecies still belongs to the species, but has just been further classified.
Amanda M

Species/Hybrids: (Jackie Taylor)
Species: A kind of organism; species are designated by binomial names written in italics; taxonomic group whose members can interbreed
Hybrids: Are the offspring of two parents that differ in one or more heritable characteristics; offspring of two different varieties or of two different species; Offspring produced from mating plants or animals from different species, varieties, or genotypes.
References
http://wordnet.princeton.edu/perl/webwn?s=species
http://www.amfar.org/cgi-bin/iowa/bridge.html?page=H
Biology of Plants, 7th edition, Peter H. Raven, Glossary pg. G-11 & G-22

Subspecies/variant
Subspecies are a morphologically distinct subdivision of a species, especially one geographically or ecologically isolated from other such subdivisions (Oxford English Dictionary). Varieties are used as equivalent to subspecies by some botanists, or subspecies may be divided into varieties. Subspecies is indicated by the abbreviation ssp.; ie. Populus balsamifera ssp. Trichocarpa. Where as variety is indicated by the abbreviation var.; ie Pinus contorta var. contorta. (Biology of Plants, Raven pg. 221).

Specific Epithet/Genus Specific epithet is the second part of a species name (Biology of plants, 7th edition, Raven, Pg G-22) The uncapitalized Latin adjective or noun that follows a capitalized genus name in binomial nomenclature and serves to distinguish a species from others in the same genus, as saccharum in Acer saccharum (sugar maple). (http://dictionary.reference.com/browse/specific epithet) Genus is the taxonomic group between family and species in rank; genera include one or more species. (Biology of Plants, 7th edition, Raven, Pg G-10) A taxonomic category ranking below a family and above a species and generally consisting of a group of species exhibiting similar characteristics. In taxonomic nomenclature the genus name is used, either alone or followed by a Latin adjective or epithet, to form the name of a species. (http://dictionary.reference.com/browse/Genus) Specific epithet and Genus are both apart of the binomial nomenclature, of grouping and assigning names to individual things. Nicole L

Taxon/Taxonomy: Taxonomy is the ordered division of organisms into categories based on a set of characteristics used to assess similarities and differences. (Campbell Reece, 7th Edition, pg. 495) Whereas a taxon is just the general term used for any one of the taxonomic categories, such as species, class, order, phylum, etc. (Raven, G-23) In overview, taxonomy is the organization of organisms into different categories, and a taxon is the name that can be used to refer to any and all of these categories.
Amanda M

Taxonomy and Nomenclature: Taxonomy is the process in which organisms are categorized into different groups. ex. where one
would be placed which, Domain, Kingdom, Division, Class, Order, Family, Genus, and Species. It is the science of identifying, classifying, and naming an organism.(Biology Seventh edition Pg. 439) Nomenclature is the art and process of naming the organism. It is usually a Latin name, with a common suffix in each group. The name in the group Order, they all end in the suffix ales, (Ex.. argaicales). (Biology of Plants seventh edition Pg. 219)-Nick N

Type Specimen/ Type Locality:Both a type specimen and type locality are involved in identifying a new species. A type specimen is the dried plant that is kept in a herbarium and is the basis for comparing specimens to figure out if they are separate species or not (Raven, pg. 221). Type locality is the location and description of the ecosystem where the type specimen was found in the world (“Type Specimens”, San Diego Natural History Museum). According to the ICBN, to have a valid publication both of these aspects are required. This information gives scientists something to work with, and incase something happened to the type specimen, the type locality would make it possible to replace it.~Quinn

Eukaryotic/Prokaryotic: Prokaryotic and eukaryotic are what distinctly define two groups of organisms. The suffixes come from the Greek word karyon which means "kernel." Prokaryote means "before a nucleus" while eukaryote means "with a true nucleus" (Raven pg. 37). A prokaryotic cell is a cell which lacks a membrane-enclosed nucleus and membrane-enclosed organelles. This is unlike a eukaryotic cell which has a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms that have eukaryotic cells such as plants, protists, and fungi are known as eukaryotes while organisms with prokaryotic cells such as archaea and bacteria are called prokaryotes. (Campbell Reece, 7th Ed.). -- John

Enhancement: (Jessica Wrench) This is a photo of a typical eukaryotic cell. Note the prominent purple section on the left hand side of the diagram which represents the nucleus. The presence of the nucleus is extremely important because eukaryotic cells contain a nucleus and other membrane bound organelles.

Photo from: http://facstaff.uww.edu/wentzl/plantcell700.jpg

Enhancement Continued: (Jessica Wrench) This is a photo of a typical prokaryotic cell. Note the lack of nucleus and membrane bound organelles.

Photo from: http://library.thinkquest.org/C004535/media/prokaryote.gif

Eukaryotic / Prokaryotic Cells Eukaryotic cell – a cell type with a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with eukaryotic cells such as: protists, plants, fungi and animals are all called eukaryotes (Campbell & Reece, Biology 7th ed. Glossary) Prokaryotic cell - a cell type lacking a membrane-enclosed nucleus and membrane-enclosed organelles. Organisms with prokaryotic cells sich as bacteria and archaea are called prokaryotes. Eukaryotic cells are subdivided by internal membranes into various membrane-enclosed organelles. In most eukaryotes the largest organelle is the nucleus which contains the DNA for the cell and all the other organelles are located in the cytoplasm, which is the region between the nucleus and the outer membrane of the cell (Campbell & Reece, Biology 7th ed. Pg 8). They have nuclear envelopes, complex chromosomes and organelles such as the mitochondria for respiration and chloroplasts for photosynthesis, which are all surrounded by membranes. Prokaryotic cells do not have their DNA separated from the rest of the cell by an enclosure in the membrane-bound nucleus (Campbell & Reece, Biology 7th ed, pg 8). They lack a genetic envelope and do not have heir genetic material organized into complex chromosomes (Raven, Biology of Plants, pg 4). Stephanie Lauer

The difference between Prokaryotic and Eukaryotic cells is easily seen in this diagram.
http://www.cod.edu/people/faculty/fancher/ProkEuk.htm
StephL

Valid publication/Effective publication: Both of these terms are rules in the International Code of Botanical Nomenclature. Valid publication is when the name given to a new species is correct in its description. For example when Douglas fir was first named Picea taxifolia, that was not valid publication because the Douglas fir is not a spruce. Effective publication refers to where the new name is set into place. It needs to be published in a recognized, peer reviewed scientific journal. (http://www.bgbm.org/iapt/nomenclature/code/saintlouis/0010Ch2Sec1a006.htm) -Morgan Traverse

Cultivar/Naturalized tree: A cultivar and a naturalized tree are both introduced species. This means that neither of these species occurs naturally in the ecosystem in which it is growing. The difference between the two is that a cultivar cannot grow without cultivation, while a naturalized tree can grow unassisted in a natural setting. (http://www.plant-materials.nrcs.usda.gov/pubs/kspmcnl4989.pdf) This can have negative implications and create invading, noxious species taking over native species. An example of a naturalized tree that is beginning to cause problems in the west Kootenays is the black locust (Robinia pseudoacacia) which is taking over riparian areas. (J. Craig-Cental Kootenay Invasive Plant Committee. Personal conversation. July 2006) - Morgan Traverse

Domain/Kingdom (Dennis Murengi) Domain: The taxonomic category above the kingdom level; the three domains are Archaea, Bacteria, and Eukarya. (Biology of Plants 7th Edition G-7) Kingdom: One of the seven chief taxonomic categories; for example, Fungi or Planatae. (Biology of Plants 7th Edition G-12) Domain and kingdom are similar in that they are both taxonomic categories of organisms. However, they differ in their taxonomic level and in what they classify. Domain is the taxonomic level above the kingdom category. (Biology of Plants 7th Edition pg 228) In addition this taxonomic category is based on distinct lineages of life through which organisms have been evolving independently of each other. (http://www.biology-online.org/dictionary/Domain) On the other hand the taxonomic level; kingdom is immediately below the domain and bases its classification on the most basic relationships between organisms. (Biology-online.org)

Prokaryotic/Eukaryotic (Russ Fountain)
In the world of cells, there are two major groups: the prokaryotes and the eukaryotes. They are very similar in that they contain many of the same parts. However, there are a few major differences between them. Eukaryotes contain membrane-bound nuclei and other organelles, while prokaryotes lack this membrane-bound nucleus. Prokaryotes are classified in two kingdoms separate from the eukaryotes. Eukaryotes are the type of cells that make up plants and one celled organisms, but not animals. The reason that they have a membrane-bound nucleus is because they have to carry out all the processes of life, which is untrue in prokaryotes. Prokaryotes rely on many cells working together to function. While eukaryotes are radically different from one another, they do have three general parts that allow them to carry out these processes of life. These are the cell membrane, the nucleus, and other organelles. The organelles are very important to the cells functioning. (Essortment. “Prokaryotes and Eukaryotes” http://ks.essortment.com/prokaryoteseuka_rgbo.htm)

Home page for Dendrology Terminology Glossary

GaryHunt — Wed, 28 Nov 2007 10:49:59 CST

This is a Dendrology glossary wiki. We will use it to make a glossary of
important terminology that will help us to learn the language of dendrology.

Your assignment
You will add information to the wiki in three different ways described below. For more detailed information and directions on how to write your entries, see the rubric and examples posted on WebCT.

A. Definitions
Eligible words are listed at the end of each lecture and are also listed at the top of each wiki page. From the total vocabulary list from all the lectures for the semester, you will make glossary-style definitions for five words or terms of your choice.

A glossary-style definition consists of a basic definition with some added explanation, examples, or an illustration. See the document posted on WebCT for examples of definitions

Your definitions must be in the context of our lectures and the subject of dendrology. For example, the word “annual” has different meanings in different situations. In botany, it refers specifically to a type of plant lifecycle. Try to relate the definitions you find in your references to our lecture discussions.

If you are copying and pasting from an online dictionary or encyclopedia, you must edit the information to focus on only the meaning you want, in the context of dendrology and our class. Delete extraneous definitions and information that does not apply.

References
You must consult at least two different references for each definition you write and give these references in your definition. For example, for the word “achene,” an achene is a small one-seeded fruit which does not open (Oxford English Dictionary). Achenes can be winged or un-winged. A winged achene such as in the London Plane Tree, can also be called a samara (Raven, Biology of Plants, p. 467).

Important note: "Wikipedia" and similar wiki sites (such as Wikimedia and Wictionary) are not valid references, but a source reference that you go to from a wiki page is a valid reference. Name your references in a way that anyone can go back to them and easily see where you got the information. Class lecture notes, from dendrology or any other class, are not valid references--you must use published references.

For referencing text or an image that you found online, give the name of the website and put the link in your reference so anyone can go directly to the site.

Always start by giving the name of the term you are defining, then put your name right after the word so everyone knows who the "author" is.

Note that each page has a separate section for alphabetical definitions and comparing and contrasting.

B. Comparing and contrasting similar terms

Many words in dendrology have very similar meanings, but are different in small but important ways. For example, the difference between adhesion and cohesion, ATP and ADP, or allele and gene. To compare and contrast means you explain how two similar terms are different, and how they are similar.

From the list of eligible words, you will compare and contrast five pairs of similar words. Use words that are different from the words you defined in part A. As with the definitions, give at least two references.

Always start by giving the name of the terms you are comparing and your name.
Note that each page has a separate section for alphabetical definitions and comparing and contrasting. Insert your comparisons alphabetically by the the first word.

C. Enhancing the entries of other students

Enhancing means to change, add to, or otherwise improve on the definitions and compare-and-contrast entries of others. Read the information that others have written, and decide how you can make it better. Think about what you could add or change to improve on a definition or comparison. This could be adding additional explanation, examples, images, or illustrations.

If you add an image or illustration, explain what it shows and how it adds to or builds on the definition being enhanced. The images you add should contribute something new that builds on, or adds to the understanding of an entry. Remember that Google Images or other image search engines are not valid references; go to the original source of the image and give credit to the originator in your reference.

You be the editor and make it better—this is what a wiki is designed to do! When you add information, remember to give your source. You will enhance five entries on our wiki.

Keep a word-processed log of all your activity
First, make your entries in a Word document, and then copy and paste onto the wiki page. This way, you will have a backup of everything you do. You will submit your log of activity at each of two deadlines.

Deleting entries of other students
Under no circumstances should you delete information posted by others. If you do this by accident and cannot recover the deleted information, you must contact the person involved and let them know about it.

Format for the final submission of your word-processed document
The title is: Dendrology Terminology Glossary. Put your name right under the title.

Put your entries in the order of Definitions (first), Compare and Contrast (second), then Enhancements.

Please include all your entries from the beginning and submit five definitions, five compare and contrast, and five enhancements.

For your enhancements, first quote the definition you are enhancing, then add your enhancement and make it clear exactly where your part starts.

Insert all your images into your word-processed file in the proper places--don't just state that they are on the wiki.

Please use Times New Roman size 12 font, and one inch margins on all sides.

Deadlines
By Wednesday, Oct. 24 at 4:00 pm, you must have completed two definitions, two comparisons, and two enhancements. Submit your log to Gary as an e-mail attachment by 4:00 pm (gahunt@tru.ca)

By Thursday, November 29 you must complete all your entries and send a completed log to Gary as an e-mail attachment by 4:00 pm. Please remember to submit your file as a ".doc" file, not ".docx". You can convert your file by going to "save as" and selecting the older version of Microsoft Word.

sandbox

S_Horley — Mon, 22 Oct 2007 15:09:07 CDT

Thuja occidentalis, a species of thuja, is an evergreen coniferous tree in the cypress family Cupressaceae, native to the northeastern U.S. and southeastern Canada, from central Saskatchewan east to New Brunswick, and south to eastern Tennessee in the Appalachian Mountains.

Unlike the closely related Thuja plicata (Western Redcedar), it is only a small tree, to 10-20 m tall and 0.4 m trunk diameter (exceptionally to 30 m tall and 1.6 m diameter). The bark is red-brown, furrowed and peels in narrow, longitudinal strips. The foliage forms in flat sprays with scale-like leaves 3-5 mm long. The cones are slender, yellow-green ripening brown, 10-15 mm long and 4-5 mm broad, with 6-8 overlapping scales.
It grows naturally in wet forests, being particularly abundant in swamps where other larger and faster-growing trees cannot compete successfully. It also occurs on other sites with reduced tree competition such as cliffs.
Ref:
-Conifer Specialist Group (1998). Thuja occidentalis. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 12 May 2006.
-Gymnosperm Database:
Thuja occidentalis (http://www.conifers.org/cu/th/occidentalis.htm)
by Scott Horley.

Bristlecone pine: (Pinus Balfourianae) A small group of pine trees that can reach an age far greater than that of any other single living organism known, up to nearly 5,000 years.

These pines grow in isolated groves at and just below the tree line. Because of cold temperatures, dry soils, high winds, and short growing seasons, the trees grow very slowly. The wood is very dense and resinous, and thus resistant to invasion by insects, fungi, and other potential pests. As the tree ages, much of its vascular cambium layer may die, in very old specimens often leaving only a narrow strip of living tissue to connect the roots to the handful of live branches.
Ref:

Bailey, D. K. 1970. Phytogeography and taxonomy of Pinus subsection Balfourianae. Ann. Missouri Bot. Gard. 57: 210-249.

Richardson, D. M. (ed.). 1998. Ecology and Biogeography of Pinus. Cambridge University Press, Cambridge

Scott Horley.