Question

Which of the following leads to absorption of water by roots of plants.

• A. Capillarity
• B. Transpiration
• C. Root pressure
• D. All of the above

Answer 1

The correct option is D All of the above

Water tends to rise up inside the narrow tubes by capillary action. This is because of an attraction of water molecules to each other by a week electrostatic force. This is called the cohesive force the water molecules are also attracted to the wall of a glass capillary tube which is similar to the inside of the xylem vessel. Because of this, water rises up in the xylem vessel to some distance up dragging other water molecules present below them. This capillary rise cannot take up water to tall plants though this may be possible in very small plants.

Transpiration is the process that is responsible for the movement of water in plants. When there is an increase in transpiration, there will be greater transpiration pull generated in plants leading to increased water absorption by roots.

The root pressure within the cells of the root system causes the sap to rise through the stem to the leaves.

Hence, the correct answer is the option D.