What is the action spectrum of transpiration ?

Options

A. Green and ultra violet
B. Orange and red
C. Blue and far red
D. Blue and red

Answer

**Step-by-Step Solution:**

1. **Understanding Action Spectrum**: The action spectrum is a graph that represents the effectiveness of different wavelengths of light in driving a particular physiological process or chemical reaction. In this case, we are focusing on transpiration.

2. **Defining Transpiration**: Transpiration is the process through which plants lose water vapor from their leaves. This occurs primarily through small openings called stomata, which are found on the leaf's surface.

3. **Role of Light in Transpiration**: Light plays a significant role in the transpiration process. The presence of light influences the opening and closing of stomata, which in turn affects the rate of transpiration.

4. **Identifying Effective Wavelengths**: Research has shown that certain wavelengths of light are more effective in promoting stomatal opening and thus enhancing transpiration. The wavelengths that are most effective for this process are blue and red light.

5. **Conclusion**: Based on the understanding of the action spectrum and the role of light in transpiration, we can conclude that the action spectrum of transpiration is associated with blue and red light.

6. **Final Answer**: Therefore, the correct answer to the question is that the action spectrum of transpiration is **blue and red**.

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