Scotoactive stomata are found in

Options

A. Aloe
B. Kalanchoe
C. Sedum
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Scotoactive Stomata**: Scotoactive stomata are specialized stomata that open during the night instead of the day. This adaptation is primarily found in certain plants that thrive in arid or high-temperature environments.

2. **Reason for Night Opening**: These stomata open at night to minimize water loss through transpiration. In hot and dry conditions, opening stomata during the day would lead to excessive water loss, which can be detrimental to the plant.

3. **Plants with Scotoactive Stomata**:
- **Aloe**: This plant is known to have scotoactive stomata as it utilizes the Crassulacean Acid Metabolism (CAM) pathway for photosynthesis, which allows it to open stomata at night.
- **Kalanchoe**: Similar to Aloe, Kalanchoe also employs the CAM mechanism, allowing it to conserve water by opening its stomata at night.
- **Sedum**: This plant also follows the CAM pathway and exhibits scotoactive stomata, making it another example of a plant that opens its stomata at night.

4. **Conclusion**: Since all three plants mentioned (Aloe, Kalanchoe, and Sedum) possess scotoactive stomata due to their adaptation to arid conditions and their use of the CAM pathway, the correct answer to the question is "all of these."

**Final Answer**: Scotoactive stomata are found in Aloe, Kalanchoe, and Sedum, thus the correct option is "all of these."

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