Plant Anatomy and Physiology Chapters 33-38 Flashcards
Annuals
herbaceous plants that grow, reproduce and die in one year
Biennials
herbaceous plants that take two years to complete their life cycles before dying.
Perennials
herbaceous plants live for more than two years
Underground parts my become dormant
Woody Perennials
Many are deciduous but others can be evergreen
Vascular Plants
Organized into a root and shoot system which has stem, leaves, and in flowering plants, fruit and nuts
Plant Cells
Organized into tissues.
Simple Tissues
One kind of cell
Complex Tissues
Two or more kinds of cells
Ground Tissue System
Variety of functions, including photosynthesis, storage, and support. Composed of three tissues
Parenchyma, Collenchyma, and Sclerenchyma.
Vascular Tissue System
Conducts substances such as water, dissolved minerals, and food (dissolved sugar) throughout the plant body
Dermal Tissue System
Outer covering of a plant, provides a covering for the plant body (epidermis) woody plants have periderm
Cell Walls
Primary Cell Wall- secreted by plant, expands as cell grows.
Secondary Cell Wall- Inside the primary cell wall, between the primary cell wall and the plasma membrane.
Parenchyma
Simple tissue, found throughout plant body, cells are alive and metabolically active, cells can differentiate into other kinds of cells
Collenchyma
Very flexible, simple plant tissue, provides support in soft and nonwoody plant organs, cells are alive at maturity, primary cell walls are especially thick in the corners
Sclerenchyma
Simple plant tissue, specialized for structural support, have primary walls and thick secondary walls, thin areas in secondary walls allow for exchange of substances between adjacent living cells, mature functioning cells are dead
Sclereids
Sclerenchyma cells of variable shape common in shells of nuts and in stones of fruits
Fibers
Long, tapered cells, that occur in clumps in wood, inner bark, and leaf ribs (veins) of flowering plants
Cellulose
Polysaccharide composed of glucose units joined by B-14 bonds
Cellulose microfibril
Formed by 40 to 70 chains that lie parallel to one another and connect by hydrogen bonding
Hemicellulose
Polysaccharides that vary in composition, some are composed of xyloglucan (B-1, 4- glucose with side chains of xylose)
Pectin
Polysaccharide of a-galacturonic acid monomers
Lignin
Strengthening polymer made up of monomers derived from certain amino acids
Vascular Tissue System
Embedded into the ground tissue, transports needed materials throughout the pant via two complex tissues, xylem and phloem.
Xylem
Conducts water and dissolved minerals from roots to stems and leaves, and provides structural support
Tracheids and Vessel elements
conduct water and dissolved minerals, fibers provide support, xylem parenchyma perform storage functions
Phloem
Conducts carbohydrates formed in photosynthesis throughout the plant, and provides structural support
Sieve tube elements and Companion cells
Work together to transport carbohydrates, fibers provide additional support
Primary Growth
An increase in stem and root length, produces the entire plant body in herbaceous plants and the young, soft shoots and roots in woody trees and shrubs, occurs in apical meristems
Secondary Growth
Gymnosperms and woody eudicots have secondary growth, wood and bark make up the bulk of trees and shrub are produced by secondary growth
Vascular Cambium
layer of meristematic cells between the wood and bark of a woody plant, adds more cells to the wood and inner bark
Cork Cambium
Cylinder or irregular arrangement of meristematic cells in the outer bark, collectively cork cells, cork cambium, and cork parenchyma make up the periderm
Bark
Outermost covering of woody stems and roots, consists of all plant tissues outside the vascular cambium. Two regions, inner bark (secondary phloem) and mostly dead outer bark (periderm)
Development
In plants, all changes that take place during the entire life of an individual, cells specialize and organize into a complex organism
Cell Differentiation
Certain cells become biochemically and structurally specialized to carry out specific functions, occurs through cell determination
Cell Determination
A series of molecular events that cause a cell to progressively commit to a particular differentiation pathway
Differential Gene Expression
Determine the structure and function of the cell, can turn on or turn off genes
Leaf Terms
Petiole- attaches blade to the stem
Stipules- leaflike outgrowths at the base of the petiole
Sessile- leaves without a petiole
Axillary buds- form at the base of a leaf
Cuticle
Secreted by epidermal cells, reduces water loss from exterior walls (made primarily by cutin)
Trichomes
Some help reduce water loss, some secrete stinging irritants for deterring herbivores, some excrete excess salts
Stomata
Created by guard cells which open and close the stomata, exchange gas between leaf cells and the environment
Mesophyll Cells
Parenchyma cells packed with chloroplasts, loosely arranged, with many air spaces between them that facilitate gas exchange
Veins (Vascular Bundles)
Extend through the mesophyll, branching is extensive, mesophyll cells are no more than 2 to 3 cells away from the vein, supply photosynthetic tissue with water and minerals from roots and remove dissolved sugar to all parts of the plant
Monocot Leaf
Narrow blade, base of leaf wraps around the stem, parallel venation, some have guard cells shaped like dumbbells
Conifers (Evergreens)
Have needle shaped leaves with a thick cuticle and sunken stomata that permit gas exchange and minimize water loss
Transpiration
Increased by warm temperature, light, wind, and dry air, and decreased by humid air, it is an important part of the hydrologic cycle
Guttation
When liquid water is forced out, looks like dew drops, occurs in low-growing plants at night when stomata are closed
