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Flashcards in vascular tissue in plants Deck (16)
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what is vascular tissue

complex tissue in plants which transports fluids and nutrients around the plant


what does the xylem transport

transports water and mineral ions


what does the phloem transport

organic substances (sucrose and amino acids)


what are vascular bundles and where are they found

xylem and phloem run close to each other
stems and leaves


where are stele found



what do vascular bundles form in leaves

the mid rib and the veins


what is the function of the xylem

tissue that transports water and mineral ions from the roots to the leaves
in addition it provides strength and support to the plant


what is the structure of the xylem

xylem undergoes secondary thickening on its cell wall
a waterproof substance called lignin is deposited in a thick layer inside the cellulose cell wall
water and nutrients can no longer enter the cells and its contents die
the deal cells are hollow which allows them to act as tubes to transport water and mineral ions
there are two types of xylem - vessels and tracheides


what are xylem vessels

found only in angiosperms
the end walls of the cells break down so the cells are effectively hollow tubes
water travels easily from one cell to another
lignin is laid down in a variety of patterns which strength the cell
holes (pits) in the wall allow water to move to adjacent cells


what are xylem tracheids

found in flowering plants conifers ferns. not found in moss
they are long thin cell with tapering end walls
they also have pits in their walls


what is transpiration

plants take in water through their roots in the soil and is lost through the leaves in the transpiration steam
water enters the plants through the root hairs moving down a water potential gradient because the vacuoles of root cells contain a strong solution of dissolved substances hence a lower water potential than the soil


what is the water movement in the roots

water enters the root through the epidermal cells of the root
some of the cells are elongated into root hairs


what route is apoplast

between the root cells along the cell walls


what route is vacuolar

from vacuole to vacuole


what route is symplast

through the cell membranes cytoplasm or plasmodesmata


what is the casparian strip

as the water approaches the xylem, the apoplast pathway is blocked by a layer of cells surrounding the pericycle
endodermis cells have thickened walls with suberin
suberin found a band around these cells called casparian strips
the water is forced into the symplast pathway and through pits enters the xylem