RQ of which diet is less than unity ?

Options

A. Carbohydrate
B. Fats
C. Organic acid
D. Sugar

Answer

To determine which diet has a respiratory quotient (RQ) of less than unity, we need to understand what RQ is and how it is calculated.

### Step-by-Step Solution:

1. **Define Respiratory Quotient (RQ)**:
- RQ is defined as the ratio of carbon dioxide (CO2) produced to oxygen (O2) consumed during respiration. The formula is:
\[ RQ = \frac{\text{CO}_2 \text{ produced}}{\text{O}_2 \text{ consumed}} \]

2. **Understand the Values of RQ**:
- Different macromolecules have different RQ values:
- Carbohydrates typically have an RQ of approximately 1.0.
- Proteins have an RQ around 0.8.
- Fats have an RQ of less than 1.0, usually around 0.7.

3. **Analyze the Composition of Fats**:
- Fats are more reduced compared to carbohydrates and proteins. This means they contain a higher proportion of carbon relative to oxygen.
- During the oxidation of fats, more oxygen is required to produce the same amount of CO2 compared to carbohydrates.

4. **Conclusion**:
- Since fats require more oxygen for oxidation and produce less CO2 in comparison, their RQ is less than 1. Therefore, the diet that has an RQ of less than unity is one that is high in fats.

### Final Answer:
The diet with an RQ of less than unity is a **fat-rich diet**.

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