Valume of RQ in succulents is

Options

A. unity
B. infinite
C. less than unity
D. zero

Explanation

### Step-by-Step Solution:

1. **Understanding RQ**: RQ stands for Respiratory Quotient. It is the ratio of the volume of carbon dioxide (CO2) produced to the volume of oxygen (O2) consumed during respiration. It is calculated using the formula:
\[ RQ = \frac{\text{Volume of CO2 produced}}{\text{Volume of O2 consumed}} \]

2. **Complete Oxidation of Glucose**: In the case of complete oxidation of glucose (C6H12O6), the reaction can be represented as:
\[ C6H12O6 + 6O2 \rightarrow 6CO2 + 6H2O + \text{Energy} \]
Here, for every 6 molecules of O2 consumed, 6 molecules of CO2 are produced. Thus, the RQ is:
\[ RQ = \frac{6}{6} = 1 \]

3. **Incomplete Oxidation of Carbohydrates**: In contrast, during the incomplete oxidation of glucose, the reaction may produce organic acids instead of CO2. For example:
\[ 2C6H12O6 + O2 \rightarrow \text{Malic Acid} + \text{Water} \]
In this case, no CO2 is produced, leading to an RQ of:
\[ RQ = \frac{0}{3} = 0 \]

4. **Succulents and Their RQ**: Succulent plants often undergo incomplete oxidation of carbohydrates, leading to the formation of organic acids (like malic acid) rather than CO2. Therefore, the RQ for succulents is:
\[ RQ = 0 \]

5. **Conclusion**: Based on the above information, the volume of RQ in succulents is:
\[ \text{RQ in succulents} = 0 \]

### Final Answer:
The volume of RQ in succulents is **0**.

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