Question

The cause of guttation is mainly

• A. Root pressure
• B. Transpiration pull
• C. Osmosis
• D. Cohesive force

Answer 1

The correct option is A

Root pressure

The correct option is (A):

Explanation of the correct option:

1. The loss of water as droplets from the margin or tip of leaves of some plants is known as guttation.
2. It takes place through small stomata-like pores called hydathodes.
3. High pressure exerted by roots also causes this phenomenon, which pushes the xylem sap to move out through the hydathodes.

Explanation of the incorrect options:

Option (B):

1. Guttation generally occurs at night, during which the stomata of the leaves are closed.
2. Hence, there will be no transpirational pull.
3. Transpiration is the loss of water through stomata in the form of water vapor.

Option (C):

1. Osmosis can be defined as the movement of solvent from a region of less concentration to a region of more concentration of solute through a selectively permeable membrane.
2. Guttation is not favored by osmosis.

Option (D):

1. Cohesive forces allows water molecule to stick to their adjacent molecules.
2. Cohesive forces allow transpirational pull.

Final answer:

The cause of guttation is mainly root pressure.