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Describe the uptake and movement of water from the soil to the leaves of a tall plant till transpiration

Describe the uptake and movement of water from the soil to the leaves of a tall plant till transpiration

Answers

gregory
Water exists as a thin film in the soil between soil particles; the concentration of cell sap is greater than that of the
surrounding solution in the soil; thus drawing water molecules across the cell wall and membrane into the root hair cells; by
osmosis; water drawn into the root hair cell dilutes the cell sap/ makes it less concentrated than that in the adjacent cell into
the cortex cell; water then moves into the cortex cell; by osmosis; upto the endodermis where it passes through by active
transport; then into the root xylem ( xylem vessels of the root); the root xylem vessels conduct the water up to xylem of stem;
then into the xylem of the leaves;
Water rises up the stem by root pressure (in the xylem vessels); capillarity ; cohesion and adhesive forces; makes water
molecules move as a continuous uninterrupted column in the xylem vessels up to the leaves;
As water vaporizes from the spongy mesophyll cell their cell sap becomes more concentrated than adjacent cells; thus this
increases the osmotic pressure of the spongy mesophyll cells; as a result water flows into the spongy mesophyll cells from the
surrounding cells; which in turn take in water from the xylem vessels in the leaf veins; this creates a pull// suction force //
transpiration pull; that pull the stream of water from the xylem vessels in the stem and roots;
The transpiration pull maintains a continuous column of water from the roots to the leaves;
gregorymasila answered the question on February 23, 2018 at 11:59

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