RO value in succulents/CAM plants in night is

Options

A. >1
B. unity
C. <1
D. Zero

Answer

### Step-by-Step Solution:

1. **Understanding the Context**: In succulent plants, particularly those that use Crassulacean Acid Metabolism (CAM), the process of respiration differs from typical plants, especially during the night.

2. **Respiration Process at Night**: During the night, CAM plants do not release carbon dioxide (CO2). Instead, they convert stored carbohydrates into organic acids, such as malic acid, while utilizing oxygen (O2).

3. **Chemical Reaction**: The process can be summarized as:
- Carbohydrates + O2 → Organic Acids (e.g., Malic Acid)
- Here, CO2 is not produced, which is a key point for calculating the respiratory quotient (RQ).

4. **Calculating Respiratory Quotient (RQ)**: The formula for RQ is:
\[ RQ = \frac{\text{Volume of CO2 produced}}{\text{Volume of O2 utilized}} \]
In this case:
- Volume of CO2 produced = 0 (since no CO2 is evolved)
- Volume of O2 utilized = 3 (as oxygen is utilized in the conversion process)

5. **Substituting Values into the RQ Formula**:
\[ RQ = \frac{0}{3} = 0 \]

6. **Conclusion**: The respiratory quotient (RQ) value for succulents/CAM plants during the night is 0. This indicates that there is no carbon dioxide produced while oxygen is being utilized.

### Final Answer:
The RQ value in succulents/CAM plants at night is **0**.

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