The `CO_(2)` stored by succulents during night is used during the day time in

Options

A. Hatch & Slack pathway
B. Calvin cycle
C. CAM
D. TCA Cycle

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The question refers to how succulents utilize carbon dioxide (CO₂) that they store at night during the daytime. Succulents are plants adapted to arid environments, and they have a unique way of photosynthesis.

2. **Photosynthesis in Succulents**: Succulents utilize a process known as Crassulacean Acid Metabolism (CAM). In this process, they open their stomata at night to take in CO₂, which is then converted into organic acids.

3. **Storage of CO₂**: During the night, CO₂ is fixed into a 4-carbon compound called oxaloacetic acid, which is then converted into malic acid. This malic acid is stored in the vacuoles of the plant cells.

4. **Daytime Utilization**: During the day, when the stomata are closed to prevent water loss, the stored malic acid is converted back into CO₂. This CO₂ is then used in the Calvin cycle, which is the process of converting CO₂ into glucose.

5. **Identifying the Correct Answer**: The question asks which process the stored CO₂ is used in during the daytime. Since the CO₂ from the malic acid is utilized in the Calvin cycle, the correct answer is the third option: CAM (Crassulacean Acid Metabolism).

6. **Elimination of Other Options**:
- **Hatch and Slack Pathway**: This is associated with C4 plants, not succulents.
- **Calvin Cycle**: While CO₂ is used here, it is not the process that stores CO₂ at night.
- **TCA Cycle**: This is related to aerobic respiration, not photosynthesis.

**Final Answer**: The CO₂ stored by succulents during the night is used during the daytime in the CAM cycle.

---