Which of the following wall of guard cells is thick

Options

A. Lateral
B. Inner (ventral concave )
C. Outer ( dorsal convex )
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Guard Cells**: Guard cells are specialized plant cells located in the epidermis of leaves. They are responsible for regulating the opening and closing of stomata, which are small pores that allow for gas exchange and transpiration.

2. **Structure of Guard Cells**: Each guard cell is bean-shaped and they exist in pairs. The space between them forms the stomatal pore.

3. **Identifying the Walls**: The guard cells have two types of walls:
- **Inner Wall**: This is the wall that faces the stomatal pore.
- **Outer Wall**: This is the wall that is on the outer side of the guard cells.

4. **Comparing the Thickness of the Walls**: The inner wall of the guard cells is thicker than the outer wall. This is crucial for their function.

5. **Function of the Thick Inner Wall**: The thickness of the inner wall prevents it from bulging into the stomatal pore when the guard cells become turgid (swollen with water). If the inner wall bulges too much, it could close the stomatal pore, which would hinder gas exchange and transpiration.

6. **Conclusion**: Therefore, the correct answer to the question "Which of the following wall of guard cells is thick?" is the **inner wall**.

**Final Answer**: The thick wall of guard cells is the **inner wall**.

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