Oxidative phosphorylation occurs during electron transfer in

Options

A. Chloroplasts
B. Mitochondria
C. Ribosomes
D. Glyoxisomes

Answer

### Step-by-Step Solution:

1. **Understanding Oxidative Phosphorylation**:
- Oxidative phosphorylation is a biochemical process that produces ATP (adenosine triphosphate) through the transfer of electrons.

2. **Role of Electron Carriers**:
- In this process, electrons are transferred from electron carriers like NADH and FADH2 to oxygen (O2). These carriers are generated during earlier stages of cellular respiration.

3. **Location of the Process**:
- The key location for oxidative phosphorylation is the mitochondria, specifically within the inner mitochondrial membrane.

4. **Formation of ATP**:
- As electrons move through the electron transport chain in the mitochondria, their energy is used to pump protons (H+) across the membrane, creating a proton gradient. This gradient drives the synthesis of ATP from ADP and inorganic phosphate (Pi) via ATP synthase.

5. **Conclusion**:
- Therefore, oxidative phosphorylation occurs during the electron transfer process in the mitochondria, making it a crucial step in aerobic respiration.

### Final Answer:
Oxidative phosphorylation occurs during electron transfer in the mitochondria.

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