a special layer of cells at the base of a leaf's petiole that severs the leaf from the stem as the plant prepares for winter
abscission layer
the basic structural unit of all living things; the smallest self-maintaining self-replication biological entity
cell
the oxidation of various foods, such as glucose, within living cells of both plants and animals for the purpose of releasing energy
cellular respiration
a subtance found in the chloroplasts of plant cells that gives plants their green color and helps them to capture the energy of sunlight to manufacture food; also found in certain protozoa and bacteria
chlorophyll
a complex organelle in green plant cells in which photsynthesis occurs
chloroplasts
a jellylike fluid that serves as the fluid medium of a cell
cytoplasm
a simple sugar (C6H12O6) produced as the initial product of photosynthesis; the form of sugar found in human blood
glucose
the chemical name for table sugar (C12H22O11)
sucrose
a complex carbohydrate substace in plant cell walls, composed of long chains of glucose molecules, provides the cell with support and protection
cellulose
a complex carbohydrate molecule that consists of a long chain of simple carbohydrates
starch
a cresent-shaped cell, bordering a stoma, which expands and contracts to regulate the size of the opening; occur in pairs
guard cells
hairlike structures that cover the leaves of certain plants
leaf hairs
tiny openings or pores on the surface of a plant, especially abundant on the underside of leaves; (singular: soma)
stomata
any of the small blades on a compound leaf
leaflet
the tissue that makes up the middle portion of a leaf where most photosynthesis takes place
mesophyll
the woody tissue of a stem that carries water and dissolved minerals upward from the roots to the leaves
xylem
a point at which leaves grow from the stem of a plant
nodes
"little organ"; any of various structures within the cytoplasm of a cell that serve as the "organs" of the cell
organelles
the food-making process of green plants, in which the energy of sunlight is used to manufacture glucose from water and carbon dioxide
photosynthesis
the part of the plant that is ordinarily underground, serving to anchor the plant, to absorb nutrients, and to store food
root system
the part of a plant that is usually found above ground, holding up the leaves toward the sun for the manufacture of food and providing for the production of flowers, fruits, and seeds
shoot system
a group of similar cells which work together to accomplish the task of an organ
tissue
in biology, a structure composed of various tissues that has a definate function or functions within a system
organ
a group of structures designed to function together as a unit to perform a definite job for an organism
system
the loss of water vapor from leaves and stems of plants by means of evaporation through the stomata
tranpiration
pressure within a plant cell resulting from the intake of water that keeps the cell firmly inflated
turgor pressure
a layer of cells in the outer bark of a woody stem that produces cork tissue
cork cambium
a thin layer of meristematic tissue between the bark and wood of woody plants where new bark and wood are produced
vascular cambium
the pattern of a leaf's veins
venation
the phenomenon of a plant losing turgor pressure as a result of a lack of water and becoming limp
wilting
the vascular tissue in plants that transports food manufactured in the leaves to the rest of the plant
