Which one is wrong about the guard cells?

Options

A. They are modified ground tissue
B. They are chlorophyllous
C. Their outer wall is thin and inner wall is highly thickened
D. They regulate stomatal movement for transpiration and gaseous exchange

Answer

To determine which statement about guard cells is incorrect, we can analyze each option based on the information provided in the video transcript.

### Step-by-Step Solution:

1. **Understanding Guard Cells**:
- Guard cells are specialized cells that surround the stomatal pores on the leaf surface and regulate the opening and closing of these pores.

2. **Analyzing Statement 1**:
- The first statement claims that guard cells are modified ground tissue.
- **Correct Information**: Guard cells are actually derived from the epidermal tissue, which is a type of dermal tissue, not ground tissue. Therefore, this statement is incorrect.

3. **Analyzing Statement 2**:
- The second statement claims that guard cells are chlorophyll-less.
- **Correct Information**: Guard cells contain chlorophyll and can perform photosynthesis. Thus, this statement is also incorrect.

4. **Analyzing Statement 3**:
- The third statement discusses the structure of guard cells, stating that their outer wall is thin and their inner wall is thick.
- **Correct Information**: This is accurate; the inner wall of guard cells is indeed thicker than the outer wall, which helps in their function of regulating stomatal opening.

5. **Analyzing Statement 4**:
- The fourth statement indicates that guard cells regulate stomatal movement for respiration and gaseous exchange.
- **Correct Information**: This is true; guard cells control the opening and closing of stomata, facilitating gas exchange and transpiration.

6. **Conclusion**:
- After analyzing all statements, the first statement is confirmed to be incorrect, as it misclassifies guard cells as modified ground tissue instead of dermal tissue.

### Final Answer:
The wrong statement about guard cells is **Option 1: They are modified ground tissue**.

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