Primary electron acceptor in cyclic photophosphorylation is

Options

A. Rubisco
B. `NADP""^(+)`
C. FAD
D. Iron- Sulphur containing protien (FeS)

Answer

To answer the question about the primary electron acceptor in cyclic photophosphorylation, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis**:
- Photosynthesis is the process by which plants convert light energy into chemical energy in the form of glucose. It involves two main stages: the light-dependent reactions and the light-independent reactions (Calvin cycle).

2. **Identifying the Types of Photophosphorylation**:
- There are two types of photophosphorylation: cyclic and non-cyclic. Non-cyclic photophosphorylation involves both Photosystem I (PSI) and Photosystem II (PSII), while cyclic photophosphorylation involves only Photosystem I.

3. **Role of Photosystems**:
- In non-cyclic photophosphorylation, electrons are generated from the splitting of water in PSII and transferred to PSI, where they are ultimately used to form NADPH.
- In cyclic photophosphorylation, PSI absorbs light and energizes electrons, which are then transferred to a primary electron acceptor.

4. **Identifying the Primary Electron Acceptor**:
- In cyclic photophosphorylation, the primary electron acceptor is an iron-sulfur protein, specifically ferredoxin (FES). This protein accepts the energized electrons from PSI and facilitates their transfer to the electron transport chain.

5. **Conclusion**:
- Therefore, the primary electron acceptor in cyclic photophosphorylation is **ferredoxin (iron-sulfur containing protein)**.

### Final Answer:
The primary electron acceptor in cyclic photophosphorylation is **ferredoxin (iron-sulfur containing protein)**.

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