The value of RQ when the respiratory substance is poor in oxygen is

Options

A. (a) Zero
B. (b) Infinity
C. (c) Greater than 1
D. (d) Less than 1

Answer

To determine the value of the respiratory quotient (RQ) when the respiratory substance is poor in oxygen, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of RQ**:
- The respiratory quotient (RQ) is defined as the ratio of the volume of carbon dioxide produced to the volume of oxygen consumed during respiration.
- Mathematically, RQ = CO2 produced / O2 consumed.

2. **Identify the Types of Respiratory Substances**:
- There are three main types of respiratory substances: carbohydrates, proteins, and fats.
- Each type has a different RQ value based on how they are metabolized.

3. **RQ Values for Different Substances**:
- **Carbohydrates**: RQ = 1 (they are easily digested even with minimal oxygen).
- **Proteins**: RQ ≈ 0.9 (digested slower than carbohydrates but faster than fats).
- **Fats**: RQ = 0.7 (they require a high amount of oxygen and are digested the slowest).

4. **Analyze the Question**:
- The question specifically asks about the RQ value when the respiratory substance is poor in oxygen.
- This implies we are likely dealing with substances that require more oxygen for metabolism, such as fats.

5. **Conclusion**:
- Since fats have the lowest RQ value (0.7) and require more oxygen for their metabolism, we can conclude that when the respiratory substance is poor in oxygen, the RQ value will be less than 1.
- Therefore, the correct answer is that the RQ value is less than 1.

### Final Answer:
The value of RQ when the respiratory substance is poor in oxygen is less than 1.

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