R.Q. of malic acid is

Options

A. 1.3
B. 4
C. 0.7
D. 1

Answer

To determine the respiratory quotient (RQ) of malic acid, we can follow these steps:

### Step 1: Understand the Concept of RQ
The respiratory quotient (RQ) is defined as the ratio of the volume of carbon dioxide (CO2) produced to the volume of oxygen (O2) consumed during respiration. The formula for RQ is:
\[ RQ = \frac{\text{Volume of CO2 evolved}}{\text{Volume of O2 consumed}} \]

**Hint:** Remember that RQ varies depending on the type of substrate being metabolized.

### Step 2: Identify the Substrate
In this case, the substrate in question is malic acid, which is an organic acid. Different substrates yield different RQ values.

**Hint:** Organic acids generally have specific RQ values that can help in identifying them.

### Step 3: Recall RQ Values for Organic Acids
From biological studies, we know that organic acids typically have RQ values greater than 1. Specifically, malic acid has an RQ value of approximately 1.3. This indicates that more CO2 is produced than O2 consumed during its metabolism.

**Hint:** Look for a pattern in RQ values for different organic acids to help you remember their approximate values.

### Step 4: Compare with Other Organic Acids
For context, other organic acids have the following RQ values:
- Oxalic acid: RQ = 4
- Succinic acid: RQ = 1.41

This comparison reinforces that malic acid's RQ is consistent with the trend of organic acids having RQ values above 1.

**Hint:** Knowing the RQ values of other organic acids can help you confirm your answer.

### Step 5: Conclusion
Based on the information gathered, we conclude that the RQ of malic acid is approximately 1.3.

**Final Answer:** The RQ of malic acid is 1.3.

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