Respirometer is an instrument used to measure

Options

A. rate of respiration
B. respiratory quotient
C. both of these
D. none of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Respirometer**: A respirometer is an instrument used to measure the rate of respiration in organisms. It helps in quantifying the amount of oxygen consumed and carbon dioxide produced during the respiratory process.

2. **Identifying the Measurements**: The respirometer measures two key aspects:
- The volume of oxygen consumed by the organism.
- The volume of carbon dioxide produced as a byproduct of respiration.

3. **Relating to Respiratory Quotient (RQ)**: The respiratory quotient (RQ) is a crucial concept related to the respirometer. It is defined as the ratio of carbon dioxide produced (CO2) to oxygen consumed (O2) during respiration. The formula is:
\[ RQ = \frac{CO2 \text{ produced}}{O2 \text{ consumed}} \]

4. **Basal Metabolic Rate (BMR)**: The respirometer can also be used to measure the basal metabolic rate (BMR), which is the rate of energy expenditure per unit time by an organism at rest. The RQ helps in calculating BMR by indicating the type of substrate being metabolized (carbohydrates, fats, or proteins).

5. **Conclusion**: Therefore, the respirometer is used to measure both the rate of respiration and the respiratory quotient, which are essential for understanding metabolic processes in plants and other organisms.

**Final Answer**: A respirometer is an instrument used to measure the rate of respiration and the respiratory quotient.

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