Number of oxygen atoms reuqired for oxidation of `2 NADH_(2)` molecules in ETS is

Options

A. 1
B. 2
C. 3
D. 4

Answer

To solve the question regarding the number of oxygen atoms required for the oxidation of 2 NADH₂ molecules in the Electron Transport System (ETS), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding NADH₂ in ETS**:
- NADH₂ is a reduced form of NAD⁺ (Nicotinamide adenine dinucleotide). In the ETS, NADH₂ donates electrons to the electron transport chain, which ultimately leads to the production of ATP and water.

2. **Oxidation Process**:
- The oxidation of NADH₂ involves converting it back to NAD⁺. During this process, NADH₂ loses electrons and protons.

3. **Oxygen Requirement**:
- For every molecule of NADH₂ that is oxidized, one molecule of oxygen (O₂) is required. This is because oxygen acts as the final electron acceptor in the electron transport chain.

4. **Calculating for 2 NADH₂**:
- Since each NADH₂ requires one molecule of O₂ for oxidation, for 2 NADH₂ molecules, we will need:
\[ 2 \text{ NADH₂} \times 1 \text{ O₂/NADH₂} = 2 \text{ O₂} \]

5. **Converting O₂ to Oxygen Atoms**:
- Each molecule of O₂ contains 2 oxygen atoms. Therefore, for 2 O₂ molecules, the total number of oxygen atoms required will be:
\[ 2 \text{ O₂} \times 2 \text{ atoms/O₂} = 4 \text{ oxygen atoms} \]

### Final Answer:
The number of oxygen atoms required for the oxidation of 2 NADH₂ molecules in ETS is **4 oxygen atoms**.