he pigment, other than chlorophylls, which might be Involved in opening of stomata by light is

Options

A. phytochrome
B. carotenes
C. phycobilins
D. plastocyanin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a pigment, other than chlorophyll, that is involved in the opening of stomata by light.

2. **Identifying Stomatal Function**: Stomata are small openings on the surfaces of leaves that allow for gas exchange (oxygen and carbon dioxide) and transpiration (water vapor loss). The opening and closing of stomata are crucial for photosynthesis and maintaining water balance in plants.

3. **Role of Light in Stomatal Opening**: Stomatal opening is influenced by light, particularly red and blue wavelengths. This indicates that certain pigments can respond to light and facilitate the opening of stomata.

4. **Exploring Pigments**: The options provided include:
- **Phytochrome**: A pigment that acts as a photoreceptor and can detect light, particularly red and far-red light.
- **Carotenes**: Accessory pigments that assist in photosynthesis but do not play a direct role in stomatal opening.
- **Phycobilins**: Water-soluble pigments found in some algae, not involved in stomatal function.
- **Plastocyanin**: A copper-containing protein involved in the electron transport chain, not a pigment that detects light.

5. **Determining the Correct Answer**: Among the options, phytochrome is the only pigment that can detect light and is involved in the physiological response of stomatal opening. Therefore, the correct answer is **Phytochrome**.

6. **Conclusion**: The pigment, other than chlorophyll, that is involved in the opening of stomata by light is **Phytochrome**.

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