Number of Oxygen atoms required for complete oxidation of pyruvic acid is

Options

A. 6
B. 12
C. 3
D. 8

Explanation

To determine the number of oxygen atoms required for the complete oxidation of pyruvic acid, we can follow these steps:

### Step 1: Understand the Structure of Pyruvic Acid
Pyruvic acid (C3H4O3) is a three-carbon compound that is a key intermediate in several metabolic pathways, including glycolysis and the Krebs cycle.

### Step 2: Identify the Complete Oxidation Process
Complete oxidation of pyruvic acid involves its conversion into carbon dioxide (CO2) and water (H2O) through cellular respiration. The process includes:
1. Conversion of pyruvic acid into acetyl-CoA.
2. Entry into the Krebs cycle (Citric Acid Cycle).
3. Oxidation of NADH and FADH2 in the electron transport chain.

### Step 3: Calculate the Oxygen Requirement
1. **Krebs Cycle**: Each molecule of pyruvic acid produces 3 CO2 molecules during the Krebs cycle.
2. **Electron Transport Chain**: In the electron transport chain, oxygen acts as the final electron acceptor. Each NADH and FADH2 contributes to the consumption of oxygen.

### Step 4: Total Oxygen Atoms Required
- For the complete oxidation of one molecule of pyruvic acid:
- 3 CO2 molecules require 3 O2 molecules (since each CO2 comes from the oxidation of one carbon atom).
- Additionally, the complete oxidation of the reduced cofactors (NADH and FADH2) also requires oxygen.

In total, the complete oxidation of one molecule of pyruvic acid requires 6 oxygen atoms.

### Conclusion
Thus, the number of oxygen atoms required for the complete oxidation of pyruvic acid is **6**.

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