Differences between photophosphorylation (PP) and oxidative phosphorylation (OP) is

Options

A. In PP, synthesis is of ATP while in OP it is of ADP
B. In PP, oxygen is evolved while in OP oxygen is taken up
C. Both cannot take place in light
D. PP can take place in green leaves while OP cannot occur in green leaves

Answer

### Step-by-Step Solution

1. **Definition of Photophosphorylation (PP)**:
- Photophosphorylation is the process of synthesizing ATP using light energy. It occurs during photosynthesis in plants, specifically in the chloroplasts. The light energy is used to convert ADP and inorganic phosphate (Pi) into ATP.

2. **Definition of Oxidative Phosphorylation (OP)**:
- Oxidative phosphorylation is a metabolic pathway that uses energy released by the oxidation of nutrients to produce ATP. It occurs in the mitochondria during cellular respiration. In this process, oxygen is reduced to form water, and ATP is synthesized from ADP and Pi.

3. **Key Differences**:
- **Energy Source**:
- PP: Light energy is the driving force for ATP synthesis.
- OP: Chemical energy from the oxidation of nutrients is used.

- **Oxygen Role**:
- PP: Oxygen is produced as a byproduct (evolved).
- OP: Oxygen is consumed (taken up) to form water.

- **Location**:
- PP: Takes place in the chloroplasts of plant cells.
- OP: Takes place in the mitochondria of both plant and animal cells.

- **Process Type**:
- PP: Part of the photosynthetic process.
- OP: Part of cellular respiration.

4. **Conclusion**:
- In summary, photophosphorylation and oxidative phosphorylation are two distinct processes that differ in their energy sources, roles of oxygen, locations within the cell, and their involvement in photosynthesis versus respiration.