When a pair of electron from `NADH(H^(+))` is transported through respiratory ETS, it results in the formation of

Options

A. 2 mol. Of ATP
B. 4 mol. Of ATP
C. 3 mol. Of ATP
D. 5 mol. Of ATP.

Answer

To solve the question regarding the number of ATP molecules formed when a pair of electrons from NADH(H⁺) is transported through the respiratory electron transport system (ETS), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding NADH and its Role**:
- NADH is a reduced coenzyme produced during glycolysis and the Krebs cycle. It carries electrons to the electron transport system.

2. **Electron Transport System (ETS)**:
- The ETS is a series of protein complexes located in the inner mitochondrial membrane. It facilitates the transfer of electrons from NADH and FADH₂ to oxygen, which ultimately leads to ATP production.

3. **Oxidation of NADH**:
- When NADH donates its electrons to the ETS, it gets oxidized back to NAD⁺. This process releases energy.

4. **ATP Production**:
- The energy released during the oxidation of NADH is used to pump protons (H⁺ ions) across the mitochondrial membrane, creating a proton gradient.

5. **Chemiosmosis**:
- The protons flow back into the mitochondrial matrix through ATP synthase, a process known as chemiosmosis, which drives the conversion of ADP to ATP.

6. **ATP Yield from NADH**:
- Each pair of electrons from one molecule of NADH typically results in the production of approximately 3 ATP molecules when passed through the ETS.

7. **Final Answer**:
- Therefore, when a pair of electrons from NADH(H⁺) is transported through the respiratory ETS, it results in the formation of **3 molecules of ATP**.

### Conclusion:
The answer to the question is that the transport of a pair of electrons from NADH through the respiratory ETS results in the formation of **3 moles of ATP**.

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