A sudden increase in carbon dioxide concentration around a leaf will cause

Options

A. Wider opening
B. Increase in transpiration
C. Closure in stomata
D. Decrease in transpiration due to closure of stomata

Answer

**Step-by-Step Solution:**

1. **Understanding Stomata Function:**
- Stomata are small openings on the leaf surface, primarily surrounded by guard cells. They play a crucial role in two main processes: gaseous exchange and transpiration.

2. **Gaseous Exchange:**
- Stomata allow carbon dioxide (CO2) to enter the leaf for photosynthesis and oxygen (O2) to exit as a byproduct. This exchange is vital for plant respiration and photosynthesis.

3. **Transpiration:**
- Transpiration is the process of water vapor loss from the plant through stomata. It primarily occurs when stomata are open. If stomata are closed, transpiration is significantly reduced or halted.

4. **Effect of Increased CO2 Concentration:**
- A sudden increase in carbon dioxide concentration around a leaf indicates that there is already sufficient CO2 available for photosynthesis. In response to this excess CO2, the plant will close its stomata to prevent further intake.

5. **Closure of Stomata:**
- The closure of stomata occurs as a regulatory mechanism to maintain homeostasis within the leaf. This prevents excessive CO2 from entering, which could be detrimental to the plant.

6. **Impact on Transpiration:**
- When stomata close due to high CO2 concentration, transpiration is decreased. This is because the stomata are the pathways through which water vapor exits the leaf.

7. **Conclusion:**
- Therefore, the correct answer to the question is that a sudden increase in carbon dioxide concentration around a leaf will lead to the closure of stomata, which in turn decreases transpiration.

**Final Answer:**
- The correct option is: **Closure of stomata or decrease in transpiration due to closure of stomata.**

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