The end product of oxidative phosphorylation is

Options

A. NADH
B. Oxygen
C. ADP
D. `ATP + H_2O `

Answer

**Step-by-Step Solution:**

1. **Understanding Oxidative Phosphorylation**:
- Oxidative phosphorylation is a metabolic process that occurs in the mitochondria, where energy from the oxidation of nutrients is used to produce ATP. It involves the electron transport chain and chemiosmosis.

2. **Role of NADH and FADH2**:
- NADH and FADH2 are electron carriers that donate electrons to the electron transport chain. Their oxidation leads to the production of ATP.

3. **Electron Transport Chain (ETC)**:
- The electron transport chain is a series of protein complexes located in the inner mitochondrial membrane. As electrons pass through these complexes, energy is released, which is used to pump protons (H+) into the intermembrane space, creating a proton gradient.

4. **Formation of ATP**:
- The protons flow back into the mitochondrial matrix through ATP synthase, a process known as chemiosmosis. This flow of protons drives the conversion of ADP and inorganic phosphate (Pi) into ATP.

5. **Final Electron Acceptor**:
- Oxygen acts as the final electron acceptor in the electron transport chain. It combines with electrons and protons to form water (H2O).

6. **End Products of Oxidative Phosphorylation**:
- The main products of oxidative phosphorylation are ATP and water. Therefore, the end product of oxidative phosphorylation is ATP and water.

**Final Answer**: The end product of oxidative phosphorylation is ATP and water.

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