Chapter 5: Roots and Soils Flashcards
What do roots do?
anchor trees firmly in the soil, absorb water and minerals in solution, store and conduct
the part of an embryo in a seed that develops into a root
radicle
an immature sporophyte that develops from a zygote within an ovule or archegonium after fertilization
embryo
What are the regions of roots?
root cap, region of cell division, region of elongation, region of maturation/differentiation
a thimble-shaped mass of cells at the tip of a growing root; functions primarily in protection
root cap
area of actively dividing cells at an apical meristem
-cells are composed of an apical meristem in the center of the root tip
region of cell division
area near an apical meristem in which cells grow in length and width
region of elongation
area of maturing cells near an apical meristem
region of maturation/differentiation
area of cells in a root in which protuberances of epidermal cells can be found
root-hair zone
a colorless, starch-forming plastid found in roots and involved in gravity perception
amyloplast
the primary meristem that gives rise to the epidermis
protoderm
meristem that produces all the primary tissues other than the epidermis and stele
ground meristem
a primary meristematic tissue that differentiates into primary xylem and phloem
procambium
a tissue produced by the vascular cambium or the cork cambium
secondary tissue
a primary tissue composed mainly of parenchyma; the tissue usually extends between the epidermis and the vascular tissue
cortex
a single layer of cells surrounding the vascular tissue (stele) in roots and some stems; the cells have Casparian strips
endodermis
a band of suberin around the radial and transverse walls of an endodermal cell; blocks the passive flow of water and solutes into vascular tissue
Casparian strip
a thin-walled cell of an endodermis
passage cell
a core of tissues, including xylem and phloem, that lies to the inside of the endodermis
vascular cylinder
tissue sandwiched between the endodermis and phloem of a root; gives rise to lateral roots
pericycle
What are examples of plants with food-storage roots?
sweet potatoes, yams, water hemlocks, dandelions, salsify, carrots, beets, turnips, and radishes
What are some examples of plants with water-storage roots?
some members of the Pumpkin Family (Cucurbitaceae)
said of buds developing in internodes or on roots, or of roots developing along stems or on leaves
adventitious
spongy root extending above the surface of the water, produced by a plant growing in water; facilitate oxygen absorption
-ex: some swamp plants, such as the black mangrove and yellow water weed
pneumatophore