When P680 absorbs light, it is exited and its electrons are transferred to an electron acceptor molecule. By doing so, P680 becomes a

Options

A. strong oxidising agent
B. strong reducing agent
C. weak oxidising agent
D. weak reducing agent

Answer

**Step-by-Step Solution:**

1. **Understanding P680**: P680 is a chlorophyll molecule located in the reaction center of Photosystem II in plants. It plays a crucial role in the light-dependent reactions of photosynthesis.

2. **Absorption of Light**: When P680 absorbs light energy, it becomes excited. This excitation refers to the increase in energy level of the electrons in the chlorophyll molecule.

3. **Electron Transfer**: The excited electrons from P680 are then transferred to an electron acceptor molecule, which is pheophytin in this case. This transfer is essential for the continuation of the photosynthetic process.

4. **Change in P680**: By transferring its electrons to pheophytin, P680 loses electrons and thus becomes positively charged or electron-deficient. This process is referred to as oxidation.

5. **Resulting State of P680**: After losing electrons, P680 is transformed into a strong oxidizing agent because it now has a tendency to accept electrons from other molecules to regain its lost electrons.

6. **Role of Pheophytin**: Pheophytin, after accepting the electrons from P680, becomes reduced. It now has an excess of electrons and can participate in further reactions, such as taking electrons from water molecules (H2O) to replenish the electrons it received.

7. **Conclusion**: Therefore, when P680 absorbs light and transfers its electrons, it becomes an oxidizing agent due to its electron deficiency.

**Final Answer**: P680 becomes an oxidizing agent.

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