Reaction centre of PS I is ____ and reaction centre of PS II is___

Options

A. `P_(680),P_(700)`
B. `P_(700),P_(680)`
C. `P_(800),P_(600)`
D. `P_(700),P_(900)`

Explanation

To answer the question regarding the reaction centers of Photosystem I (PS I) and Photosystem II (PS II), we can follow these steps:

### Step-by-Step Solution:

1. **Identify Photosystem I (PS I)**:
- PS I is one of the two photosystems involved in the process of photosynthesis.
- It is primarily responsible for the absorption of light and the conversion of light energy into chemical energy.

2. **Determine the Reaction Center of PS I**:
- The reaction center of PS I is known as P700.
- This name indicates that it has a peak absorption at a wavelength of 700 nanometers.

3. **Identify Photosystem II (PS II)**:
- PS II is the other photosystem that works alongside PS I during photosynthesis.
- It plays a crucial role in the initial steps of the light-dependent reactions.

4. **Determine the Reaction Center of PS II**:
- The reaction center of PS II is known as P680.
- This indicates that it has a peak absorption at a wavelength of 680 nanometers.

5. **Formulate the Final Answer**:
- Therefore, the reaction center of PS I is P700, and the reaction center of PS II is P680.

### Final Answer:
The reaction center of PS I is **P700** and the reaction center of PS II is **P680**.

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