In `PS` I, the carrier that picks up electrons from `P_(700)` is

Options

A. Fe protein
B. Fe-S protein
C. Fe-Cu protein
D. Fe-Mg protein.

Answer

To answer the question regarding which carrier picks up electrons from P700 in Photosystem I (PS I), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosystem I (PS I)**:
- PS I is a crucial component of the photosynthetic process, specifically involved in the light-dependent reactions. It contains chlorophyll-a molecules that absorb light, primarily at a wavelength of 700 nm.

2. **Role of P700**:
- P700 refers to the special pair of chlorophyll-a molecules in PS I that are responsible for the initial steps of photosynthesis. When these molecules absorb light, they become excited and release electrons.

3. **Electron Transport Chain**:
- After the electrons are released from P700, they are transferred through a series of electron carriers in the thylakoid membrane. This process is known as the electron transport chain.

4. **Identifying the Primary Electron Acceptor**:
- The primary electron acceptor that picks up the electrons from P700 is an important component of this chain. In the case of PS I, the primary electron acceptor is ferredoxin.

5. **Composition of Ferredoxin**:
- Ferredoxin is an iron-sulfur protein (FeS protein) that plays a key role in transferring electrons from PS I to other molecules in the photosynthetic pathway.

6. **Conclusion**:
- Therefore, the carrier that picks up electrons from P700 in PS I is the FeS protein.

### Final Answer:
The carrier that picks up electrons from P700 in PS I is **FeS protein**.

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