NEET BIOLOGY

Detailed explanation-1: -The bulk of water absorbed and transported through plants is moved by negative pressure generated by the evaporation of water from the leaves (i.e., transpiration)-this process is commonly referred to as the Cohesion-Tension (C-T) mechanism.

Detailed explanation-2: -As transpiration occurs, it deepens the meniscus of water in the leaf, creating negative pressure (also called tension or suction). The tension created by transpiration “pulls” water in the plant xylem, drawing the water upward in much the same way that you draw water upward when you suck on a straw.

Detailed explanation-3: -Transpiration is a process that involves loss of water vapour through the stomata of plants. The loss of water vapour from the plant cools the plant down when the weather is very hot, and water from the stem and roots moves upwards or is ‘pulled’ into the leaves.

Detailed explanation-4: -As molecules line up for absorption in the xylem tissues, the first molecule is lost by the plant owing to transpiration. This causes a negative pressure in the leaf, which aids in the movement of water up the xylem from the roots.

Detailed explanation-5: -Capillary action helps bring water up into the roots. But capillary action can only “pull” water up a small distance, after which it cannot overcome gravity. To get water up to all the branches and leaves, the forces of adhesion and cohesion go to work in the plant’s xylem to move water to the furthest leaf.