VERSION ACTUAL EXAM QUESTIONS AND WELL
ELABORATED ANSWERS (100% CORRECT VERIFIED
ANSWERS) |GUARANTEED PASS A+ (BRAND NEW!!)
Meristem - ANSWER: Specialized zones where the process of cell division takes place.
Primary and Secondary
differentiation - ANSWER: Change in cell structure to assume a variety of roles
Tree Organs - ANSWER: leaves, stems, roots, flowers, fruit
Primary meristems - ANSWER: where primary growth occurs. Growth of shoots and
roots from apical meristems
Primary Growth - ANSWER: growth of shoots and roots from apical meristems
Secondary meristems - ANSWER: tissue associated with diameter growth in stems,
branches, roots, and producing wood--> secondary growth. Palms lack secondary
growth
apical meristem - ANSWER: meristems located at the ends of shoots and roots. In
shoots they are found inside buds
Buds - ANSWER: Where apical meristem is found in shoots. Meristematic tissue is
protected by overlapping scales
Cambium - ANSWER: Secondary or lateral meristem. Thin sheath of dividing cells
that produces th cells that will become the vascular system of the tree. Produces
xylem and phloem
cork cambium - ANSWER: Second lateral meristem after cambium. This produces the
bark or periderm
periderm - ANSWER: bark
Cellulose - ANSWER: Structural component of primary cell wall. Most common
organic compound on Earth.
Lignin - ANSWER: Component of plant cells with cellulose. When formed in the cell
walls of the wood, it provides the strength and rigidity
Xylem - ANSWER: Wood of tree. Composed of both living and dead elements:
symplasm and apoplasm
,Xylem functions - ANSWER: 4.
1. conduction of water and dissolved minerals
2. support of the weight of the tree
3. storage of carbohydrate reserves
4. defense against the spread of disease and decay
Symplasm - ANSWER: Living tissue of the tree
Apoplasm - ANSWER: Nonliving tissue of the tree
Xylem of Gymnosperms - ANSWER: (pines and spruces) Composed of
1. tracheids
2. fibers
3. parenchymal cells
Tracheids - ANSWER: conduct water and provide mechanical support. Part of the
xylem. Elongated dead cells with pointy ends and thickened walls. Less efficient than
vessels for water conduction
Fibers - ANSWER: Part of xylem. Provide mechanical strength
Parenchymal cells - ANSWER: -living cells interspersed among the other xylem cells.
Those located in the outer layers of the xylem store carbs, help defend agaisnt
decay, and have a structural function across the grain.
-Are more abundant in hardwood trees and are arranged close to the vessel
elements
Xylem of Hardwoods - ANSWER: 1. Tracheids
2. fibers
3. parenchymal cells
4. Vessels
Vessels - ANSWER: Primary conducting elements of hardwoods. Stacks of dead,
hollow cells that from long tubes of water-conducting elements. Much more efficient
in water conduction than are tracheids.
Ring porous - ANSWER: Characteristic of trees where they form wide vessels early in
the growing season and narrower vessels later: Ulmus,quercus, fraxinus and others.
Ring Porous Species - ANSWER: Ulmus, Quercus, Fraxinus
Diffuse Porous - ANSWER: Characteristic where the tree produces vessels of uniform
size throughout growing season. Species include: Acer, Platanus, and Populus, and
others.
Diffuse porous species - ANSWER: Acer, Platanus, Populus
, Growth rings - ANSWER: Visible in xylem when tree viewed in cross section. The
result of seasonal production of xylem by the cambium. Appear as rings because the
relative size and density of the vascular tissues change throughout the growing
season. As season goes on, cells become smaller.
Nonporous Wood - ANSWER: What conifers ar conisdered as opposed to diffuse or
ring porous given their lack of vessels.
Sapwood - ANSWER: xylem that conducts water. Contains many living parenchymal
cells.
Heartwood - ANSWER: Older xylem near the center of a woody stem that no longer
conducts water
Phloem - ANSWER: -Living vascular tissue that carries sugar and organic substances
throughout a plant.
-Moves carbs produced in the leaves throughout the plant for storage or
consumption. Movement is relatively slow and occurs along a pressure gradient-->
requires energy
Composition of Phloem - ANSWER: Composed primarily of living cells
1. Sieve cells: living cells in phloem of conifers
2. Sieve tube elements and companin cells: living cells in phloem of hardoods.
Unlike xylem which increases diameter of tree, old phloem is crushed and living cell
contents are reabsorbed and cell walls incorporated into bark layers
Radial vs. Longitudinal Transport - ANSWER: Phloem and xylem transport
longitudinally and radially
Rays - ANSWER: Radial transport cells made up of parenchyma cells that grow
radially across the grain in small layers that extend across the growth increments of
xylem and into the phloem
Function of rays - ANSWER: -First define Ray
1.transport carbs and other compound into sapwood
2. store carbs as starch
3. assist in restricting decay in wood tissue
Bark - ANSWER: Outer covering of a tree's branches, stems, and soemtimes, roots.
-Composed of protective tissues that moderate temp, injury and water loss
-Outerbark composed of non-functional phloem and corky tissues.
-full of wax and oils
Lenticels - ANSWER: Small openings in the bark that permit gas exchange
Twigs - ANSWER: small stems that provide support structures for leaves, fruits, and
flowers. Supported by branches, which are supported by trunk