Question

Water will be absorbed by root hair when

• A. Concentration of solutes in the cell sap is high.
• B. Plant is rapidly respiring.
• C. They are separated from soil by a permeable membrane.
• D. Concentration of salts in the soil is high.

Answer 1

Answer: (A)

Concentration of solutes in the cell sap is high.

Absorption of water by roots is done by root hairs. A root hair contains cell sap, having high concentration of salts as compared to outside soil water. Due to this, water from outside moves inside the root hairs along the concentration due to osmosis. This absorbed water reaches vascular tissues and is finally supplied to all parts of plants.

So, the correct answer is 'Concentration of solutes in the cell sap is high.'