When do the desert plants take up carbon dioxide ?

Options

A. During early morning
B. During day
C. During night
D. All the time

Explanation

**Step-by-Step Text Solution:**

1. **Understanding Stomata**: Stomata are tiny openings on the surface of leaves that allow for gas exchange. They play a crucial role in photosynthesis by taking in carbon dioxide (CO2) and releasing oxygen (O2).

2. **Adaptation of Desert Plants**: Desert plants have adapted to survive in arid conditions where water is scarce. One of their key adaptations is the timing of when they open their stomata.

3. **Nighttime CO2 Uptake**: Desert plants typically open their stomata at night instead of during the day. This is because temperatures are cooler at night, and humidity levels are often higher, which reduces water loss.

4. **Preventing Water Loss**: During the daytime, desert plants keep their stomata closed to prevent excessive water loss through transpiration. This is crucial for their survival in hot and dry environments.

5. **Photosynthesis Process**: By taking in CO2 at night, desert plants can store it and use it during the day for photosynthesis when sunlight is available, even though their stomata are closed.

6. **Conclusion**: Therefore, desert plants take up carbon dioxide primarily at night to conserve water and effectively carry out photosynthesis during the day.

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