In light reaction, pigments are organised into two photochemical complexes called

Options

A. Photosystem - I and Photosystem - II
B. Light harvesting complexes
C. Antennae
D. None of the above

Answer

To solve the question regarding the organization of pigments in the light reaction, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Light Reactions**:
- The light reactions of photosynthesis occur in the thylakoid membranes of chloroplasts. They involve the absorption of light energy by pigments.

2. **Identifying Pigments**:
- The primary pigments involved in the light reactions are chlorophyll a, chlorophyll b, and carotenoids. These pigments play a crucial role in capturing light energy.

3. **Formation of Photochemical Complexes**:
- These pigments are organized into structures known as photochemical complexes.

4. **Naming the Complexes**:
- The two main photochemical complexes in the light reactions are called Photosystem I (PSI) and Photosystem II (PSII).

5. **Function of the Complexes**:
- Photosystems are responsible for the initial steps of photosynthesis, where light energy is converted into chemical energy.

6. **Conclusion**:
- Therefore, the correct answer to the question is that pigments are organized into two photochemical complexes called Photosystem I and Photosystem II.

### Final Answer:
In light reactions, pigments are organized into two photochemical complexes called **Photosystem I (PSI) and Photosystem II (PSII)**.

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