Which one is the driving force for the process of passive absorption of water in roots

Options

A. Root pressure
B. Transpiration in leaves
C. Activity of aquaporins
D. Increase in imbibitin pressure in root cells

Answer

**Step-by-Step Solution:**

1. **Understanding Passive Absorption**: Passive absorption of water in plants refers to the uptake of water by roots without the expenditure of energy. This process relies on physical forces rather than metabolic energy.

2. **Role of Transpiration**: The primary driving force for passive absorption is transpiration. Transpiration is the process through which water evaporates from the surface of leaves into the atmosphere.

3. **Transpiration Pull**: As water evaporates from the leaves, it creates a negative pressure (or tension) within the leaf's air spaces. This negative pressure pulls more water upward from the roots through the xylem vessels.

4. **Water Movement**: The movement of water from the soil into the roots occurs due to the difference in water potential. The water potential in the soil is higher than that in the root cells, allowing water to move passively into the roots.

5. **Conclusion**: Therefore, the driving force for the passive absorption of water in roots is the transpiration pull created by the evaporation of water from the leaves.

**Final Answer**: The driving force for the process of passive absorption of water in roots is transpiration.

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