High `CO_(2)` concentration in leaf interior will cause

Options

A. Stomatal opening
B. Stomatal closure
C. No effect on stomata
D. Stomata are destroyed .

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of CO2 in Photosynthesis:**
- Carbon dioxide (CO2) is a key reactant in the process of photosynthesis, which occurs in the chloroplasts of plant cells. When CO2 concentration is high, it indicates that the plant is potentially photosynthesizing efficiently.

2. **Guard Cells and Stomatal Regulation:**
- Stomata are small openings on the leaf surface that allow for gas exchange (CO2 in, O2 out). They are surrounded by guard cells that control their opening and closing.

3. **Effect of High CO2 Concentration:**
- When there is a high concentration of CO2 in the leaf interior, it suggests that the plant may not need to take in more CO2 for photosynthesis. As a result, the guard cells will respond to this high concentration.

4. **Starch Formation in Guard Cells:**
- The guard cells require starch to maintain their turgor pressure, which is necessary for them to remain open. High levels of CO2 can lead to a decrease in the rate of photosynthesis, resulting in lower starch production.

5. **Closure of Stomata:**
- With reduced starch levels in the guard cells, they lose turgor pressure and consequently close the stomata. This prevents further CO2 from entering the leaf, which is a response to the already high internal CO2 concentration.

6. **Conclusion:**
- Therefore, the correct answer to the question is that high CO2 concentration in the leaf interior will cause stomatal closure.

**Final Answer: Stomatal Closure**

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