Which statement about oxidative phosphorylation is not true?

Options

A. The inner mitochondrial membrane has 5 distinct respiratory or enzyme complexes
B. CoQ links complex I and II, and cyt c links complex III with complex IV
C. FAD, FMN, FeS clusters and copper are other cofactors that participitate in electron transfer
D. 38 ATPs are formed when one pair of protons return to matrix via `F_(0)` of ATP synthase

Answer

To determine which statement about oxidative phosphorylation is not true, we need to analyze the provided information step by step.

### Step-by-Step Solution:

1. **Understanding Oxidative Phosphorylation**:
- Oxidative phosphorylation occurs in the inner mitochondrial membrane and is a crucial part of cellular respiration. It involves the electron transport chain and ATP synthesis.

2. **Identifying the Components**:
- There are five distinct respiratory enzyme complexes in the inner mitochondrial membrane:
- Complex I: NADH dehydrogenase
- Complex II: Succinate dehydrogenase (also known as coenzyme Q)
- Complex III: Cytochrome bc1 complex
- Complex IV: Cytochrome c oxidase
- Complex V: ATP synthase

3. **Co-factors Involved**:
- Important co-factors in the electron transport chain include FAD, FMN, iron-sulfur clusters, and copper ions. These co-factors play essential roles in the electron transfer process.

4. **ATP Production**:
- The total ATP yield from complete cellular respiration (including glycolysis, the Krebs cycle, and oxidative phosphorylation) can be up to 38 ATP molecules in eukaryotic cells. However, this total is not produced by a single pair of protons returning to the ATP synthase complex.

5. **Analyzing the Statements**:
- The statement that claims "38 ATP are formed when one pair of protons return to the matrix F0 of ATP synthase" is incorrect. The total ATP yield is a cumulative result of multiple protons moving through ATP synthase, not just one pair.

6. **Conclusion**:
- Therefore, the statement about 38 ATP being formed from one pair of protons is the incorrect statement regarding oxidative phosphorylation.

### Final Answer:
The statement that is not true about oxidative phosphorylation is: "38 ATP are formed when one pair of protons return to the matrix F0 of ATP synthase."