RQ means

Options

A. ratio of `CO_2` produced to `O_2` utilized
B. consumption of `CO_2` per minute
C. consumption of `O_2` per minute
D. ratio of heat and `O_2` consumption

Answer

**Step-by-Step Solution:**

1. **Definition of RQ**: RQ stands for Respiratory Quotient. It is a term used in physiology to describe the ratio of carbon dioxide (CO2) produced to oxygen (O2) consumed during respiration.

2. **Understanding the Concept**: The respiratory quotient is calculated by measuring the amount of CO2 produced by the body and the amount of O2 consumed over a specific period.

3. **Formula**: The formula for RQ can be expressed as:
\[ RQ = \frac{\text{CO2 produced}}{\text{O2 consumed}} \]

4. **Example Calculation**: For example, if the body consumes 100 units of O2 and produces 90 units of CO2, the RQ would be calculated as:
\[ RQ = \frac{90}{100} = 0.9 \]
This means that for every unit of oxygen consumed, 0.9 units of carbon dioxide are produced.

5. **Significance of RQ**: The value of RQ can provide insights into the type of substrate being metabolized for energy. For instance:
- An RQ of 1 indicates that carbohydrates are being metabolized.
- An RQ of 0.7 suggests fat metabolism.
- An RQ of around 0.8 indicates protein metabolism.

6. **Conclusion**: Therefore, RQ is an important physiological parameter that helps in understanding metabolic processes in the body.

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