Cohesion-tension theory is related to

Options

A. Respiration
B. Ascent of sap
C. Transpiration
D. Photosynthesis

Answer

**Step-by-Step Solution:**

1. **Understanding Cohesion-Tension Theory**: The cohesion-tension theory explains how water moves through plants, particularly from the roots to the leaves. It is primarily related to the process of transpiration.

2. **Ascent of Sap**: The theory is often referred to as the "ascent of sap." This term describes the upward movement of water (sap) within the plant, which is essential for nutrient transport and maintaining plant structure.

3. **Role of Transpiration**: Transpiration is the process where water evaporates from the leaves of the plant. This creates a negative pressure (tension) in the leaf, which pulls water upward from the roots through the xylem vessels.

4. **Cohesion of Water Molecules**: Water molecules exhibit cohesion, meaning they tend to stick to each other due to hydrogen bonding. This property allows a continuous column of water to be maintained in the xylem vessels, preventing the column from breaking.

5. **Capillary Action**: The cohesion of water molecules also contributes to capillary action, which helps in the upward movement of water through narrow xylem vessels. This action allows water to move against gravity.

6. **Movement Through Plasmodesmata**: Water can move between plant cells through plasmodesmata, which are small channels that connect plant cells. This movement occurs without crossing the cell wall or membrane, facilitating efficient transport.

7. **Conclusion**: Therefore, the cohesion-tension theory is fundamentally related to the ascent of sap in plants, driven by transpiration and the cohesive properties of water.

**Final Answer**: The cohesion-tension theory is related to the ascent of sap.

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