plasmodesmata

endoderml cells

symplast

apoplast

the pressure flow of sap through phloem

a water vapor break in the coloumn of xylem sap

a higher water potential of the leaves than of the roots

a root pressure causing water to flow up through xylem faster than it can lost by transpiration

transpiration

plasmodesmata

cohesion

tension

hydrogen bonding between molecule of water

the pull of the water column as water evaporates from surfaces of mesophyll cells

tension within the xylem caused by negative pressure

the high surface tension of water

attraction of water molecules to hydrophilic walls of narrow xylem tubes

bulk flow

cotransport using proton gradient

diffusion

apoplast

tension created by the differences in pressure in the source and sink

active transport of sucrose through the sieve tube cells driven by proton pumps

the hydrolysis of starch to sucrose in the mesophyll cells that raise their water potential and drives the bulk flow of sap to the sink

osmotic movement of water into the sucrose loaded sieve tube members creating a higher pressure in the source than in the sink

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active transport of sucrose driven by passive transport of H+

activated proton pump create H+ gradient

increase water potential in the phloem

increase pressure in the phloem

loading sugar into sieve tube reduce its water potential

water enter the sieve tube by osmosis

tension created by differences in pressure in the source and sink

evaporation of water and active transport of sucrose from the sink

storage organ

point of delivery from source

site of sucrose manufacture

have mesophyll cells

minerals actively pump out of root

root has higher water potential that soil

soil has high water potential than root

soil has low water potential

not affected by water and minerals

its allow movement of water by apoplast

Transport only the needed minerals from soil into xylem

Prevents the ions from leaking back into the cortex and soil