Which of the following is not required for transpiration of water through xylem?

a) Root pressure.

b) ATP.

c) Evaporative pressure.

d) Capillary action.

b) ATP.

Explanation:

Transpiration is a passive process which does not require any energy input i. e. ATP. During transpiration, the water evaporates through leafs due to the impact of sunlight because of which water is lost from the surface of leafs. The water through xylem rises because of the capillary action which exists because of the force of adhesion existing between water molecules and the walls of xylem. Apart from this, cohesive force between water molecules also play important role in transpiration and root pressure plays a very important role in forming continuous chain of water molecules so that cohesive force could be established in the xylem tissue.

Here, it may be noted that when a force exists between molecules of same substance it is known as cohesive force but if a force exists between the molecules of different substances it is known as adhesive force.