Guard cells help in

Options

A. Transpiration
B. Guttation
C. Fighting against infection
D. Protection against grazing

Answer

**Step-by-Step Text Solution:**

1. **Introduction to Guard Cells:**
- Guard cells are specialized cells located in the epidermis of plant leaves. They play a crucial role in regulating gas exchange and water loss in plants.

2. **Understanding Stomata:**
- Guard cells surround small openings called stomata. The stomata are essential for the exchange of gases (like oxygen and carbon dioxide) and for transpiration.

3. **Function of Guard Cells:**
- The primary function of guard cells is to control the opening and closing of stomata. This regulation is vital for maintaining water balance in the plant.

4. **Mechanism of Action:**
- When the plant has sufficient water, guard cells take up water and swell, causing the stomata to open. This allows water vapor to escape (transpiration) and gases to enter or exit.
- Conversely, when water is scarce, guard cells lose water and shrink, leading to the closing of the stomata. This helps to conserve water within the plant.

5. **Role in Transpiration:**
- Transpiration is the process of water vapor loss from the plant to the atmosphere. Guard cells play a crucial role in this process by regulating the stomatal openings, thus controlling the rate of transpiration.

6. **Conclusion:**
- In summary, guard cells are essential for the process of transpiration by regulating the opening and closing of stomata, which helps in maintaining water balance and facilitating gas exchange in plants.

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