With the decrease in atmospheric pressure, the rate of transpiration will

Options

A. increase
B. decrease slowly
C. decrease rapidly
D. remain unaffected

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**: Transpiration is the process by which water vapor is lost from the aerial parts of plants, primarily through small openings called stomata.

2. **Effect of Atmospheric Pressure**: Atmospheric pressure refers to the weight of the air surrounding us. When atmospheric pressure decreases, it creates a difference in pressure between the inside of the leaf and the outside environment.

3. **Pressure Gradient**: Air moves from areas of higher pressure to areas of lower pressure. In this case, when atmospheric pressure decreases, the pressure inside the leaf becomes relatively higher compared to the outside environment.

4. **Movement of Water Vapor**: Due to the higher pressure inside the leaf, water vapor (along with air) moves from the leaf to the outside atmosphere. This movement is facilitated by the pressure difference created by the decrease in atmospheric pressure.

5. **Increase in Transpiration Rate**: As a result of the increased movement of water vapor from the leaf to the atmosphere, the rate of transpiration increases.

6. **Conclusion**: Therefore, with the decrease in atmospheric pressure, the rate of transpiration will increase.

**Final Answer**: The rate of transpiration will increase with the decrease in atmospheric pressure.

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