Pyruvate dehydrogenase activity during aerobic respiration requires:-

Options

A. Calcium
B. Iron
C. Cobalt
D. Magnesium

Answer

To solve the question regarding the requirement for pyruvate dehydrogenase activity during aerobic respiration, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of Pyruvate Dehydrogenase**:
- Pyruvate dehydrogenase is an enzyme that catalyzes the conversion of pyruvate into acetyl coenzyme A (acetyl-CoA), which is a crucial step in aerobic respiration.

2. **Identify the Role of Cofactors**:
- Enzymes often require cofactors to function properly. These cofactors can be metal ions or organic molecules that assist in the enzyme's activity.

3. **Analyze the Given Options**:
- The options provided are calcium, iron, cobalt, and magnesium. We need to determine which of these is specifically required for the activity of pyruvate dehydrogenase.

4. **Research the Specific Cofactor for Pyruvate Dehydrogenase**:
- Pyruvate dehydrogenase is known to require magnesium ions (Mg²⁺) as a cofactor for its activity. This is a well-documented fact in biochemistry.

5. **Conclude the Correct Answer**:
- Based on the information gathered, the correct answer to the question is that pyruvate dehydrogenase activity during aerobic respiration requires magnesium.

### Final Answer:
- The correct option is **4. Magnesium**.

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