The electron released from PS I is first accepted by :-

Options

A. Plastoquinone
B. FRS
C. Cytochrome
D. Plastocyanin

Answer

### Step-by-Step Solution:

1. **Understanding Photosystems**: Photosynthesis occurs in two main phases: the light-dependent reactions and the light-independent reactions (Calvin cycle). The light-dependent reactions take place in the thylakoid membranes of the chloroplasts and involve two photosystems: Photosystem I (PS I) and Photosystem II (PS II).

2. **Role of Photosystem I (PS I)**: In PS I, the primary pigment is chlorophyll a, which absorbs light primarily at a wavelength of 700 nm. This absorption of light energy excites electrons in the chlorophyll.

3. **Electron Excitation**: When light is absorbed by PS I, it excites a pair of electrons, which are then transferred to a primary electron acceptor.

4. **First Electron Acceptor**: The first molecule to accept the excited electrons from PS I is known as Ferredoxin (often abbreviated as Fd). This molecule is a type of iron-sulfur protein that plays a crucial role in the electron transport chain.

5. **Electron Transport Chain**: After being accepted by Ferredoxin, the electrons continue through a series of other acceptors, including Plastoquinone (PQ), Cytochrome (CY), and Plastocyanin (PC), but the question specifically asks for the first acceptor.

6. **Conclusion**: Therefore, the electron released from PS I is first accepted by Ferredoxin (FRS).

### Final Answer:
The electron released from PS I is first accepted by Ferredoxin (FRS).

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