Question

Explain how water is taken up by the plant roots and transported throughout the plant. Show the pathways and explain the mechanisms used to reach all parts of the plant.

Answer 1

ANSWER-

water is being taken up by the roots with the help of simple diffusion , the cells present on the roots takes up the water by simple diffusion and then the water is being transported to the rest of the plant via apoplastic and symplastic pathway.

a rough Diagrammatic representation is being given below of apoplast and symplast pathway.

symplast pathway is pathway which occurs through the inside the cell, and apoplast pathway occurs through the periphery of the cell,ie , from the plasma membrane.

as one can see in the above diagram, that the transport starts with symplast and apoplast and once the casparian strips occurs , the transport becomes symplast.

and then enters into the xylem,xylem is present in the main stem of the plant and from.here the water is being transported to the whole plant.

there are various theories for the same, like transpiration pull ,ascent of sap and others.

out of all these, ascent of sap is the most accepted one.

in this due to capillary action of plant water droplets which move up and stick together with the cohesion and adhesion forces and by capillary action. this capillary action creates so much of suction pressure and up pull that the water can reach up to heights of several feets. once reaching above heights, it is transported into the leaves with simple diffusion against the flow of gravity.

this is the basic mechanism of water transport in the plant.

a rough diagrammatic representation is being given below to understand the concept better.

as one can figure out from the above image that how various factors plays role in the water transportation, from including cohesion adhesion forces, transpiration rate, suction pressure, root pressure, capillary action and others.and the combination of all these results in the transport of water