The inner wall of each guard cell, towards the pore or stomatal aperture, is

Options

A. thick and elastic
B. thin and elastic
C. thin and inelastic
D. thin and inelastic

Answer

**Step-by-Step Solution:**

1. **Understanding Guard Cells**: Guard cells are specialized cells that surround the stomatal pores on the surface of leaves. They play a crucial role in regulating the opening and closing of these pores.

2. **Identifying the Stomatal Aperture**: The stomatal aperture is the opening that allows for gas exchange (such as oxygen and carbon dioxide) and transpiration (the loss of water vapor) to occur.

3. **Examining the Structure of Guard Cells**: Each guard cell has an inner wall that faces the stomatal pore. This wall is important for the function of the guard cells.

4. **Characteristics of the Inner Wall**: The inner wall of each guard cell towards the stomatal aperture is described as being thick and elastic. This structure allows the guard cells to change shape effectively, which is essential for opening and closing the stomatal pore.

5. **Functionality of Guard Cells**: When the turgor pressure within the guard cells increases, they swell and the stomatal pore opens. Conversely, when the turgor pressure decreases, the guard cells become flaccid, and the stomatal pore closes. This mechanism is vital for regulating water loss and gas exchange.

6. **Conclusion**: Based on the structure and function of guard cells, the correct answer to the question is that the inner wall of each guard cell towards the stomatal aperture is **thick and elastic**.

**Final Answer**: The inner wall of each guard cell, towards the pore or stomatal aperture, is **thick and elastic**.

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