abeka biology pgs 57-60

bold and italicized terms

root system that penetrates the ground with relatively little branching

taproots

another name for taproots

primary roots

taproots that enlarge to store large quantities of food

fleshy roots

examples of plants with fleshy roots

carrots, beets, dandelions

roots of grasses and monocots that have no main section but spread out with thin roots forming a tangled mass

fibrous roots

roots that arise from the stem

adventitious roots

protective layer covering the outer part of a root

epidermis

long, finger-like projections developed from the epidermis

root hairs

the root's food storage region inside the epidermis

root cortex

contains xylem and phloem tissues (surrounded by the cortex)

central vascular cylinder

another name for the central vascular cylinder

stele

main growing region near the tip of the root / responsible for forming the epidermis, cortex, and vascular cylinder

apical meristem

region closest to the end of the root tip

meristematic region

region just above the meristematic region/ cells increase in length, pushing the root further into the soil

region of elongation

region of growth in which cells organize into the vascular cylinder (root hairs grow from this section)

maturation region

at the tip of the root, providing a covering

root cap

growth later of meristematic cells between the xylem and the phloem

vascular cambium

forms beneath the epidermis in later stages of secondary growth

cork cambium

allows some substances to diffuse through it but not other substances

semipermeable

one-way diffusion through a semipermiable membrane

osmosis

upward flow of water and absorbed minerals through the xylem tubes

sap stream

the osmotic force that helps move water to the vascular cylinder

root pressure

the upward movement of liquids through a very narrow tube

capillarity

attracrion of water molecules to the surface of the xylem tubes (opposite attraction)

adhesion

molecules' attraction to each other (same attraction)

cohesion

cheif force that draws water up the stem

transpiration pull