The splitting of water molecule is associated with

Options

A. Photosystem I
B. Photosystem II
C. Cytochromes complex
D. Coupling factor

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the association of the splitting of water molecules during photosynthesis. Specifically, we need to identify which component is responsible for this process.

2. **Identifying the Process**: The splitting of water is known as photolysis. This process occurs when water molecules are split into oxygen, protons, and electrons under the influence of light.

3. **Location of the Process**: Photolysis occurs on the inner side of the thylakoid membrane in chloroplasts during the light-dependent reactions of photosynthesis.

4. **Role of Photosystem II**: During the light reactions, particularly in the Z-scheme, electrons are excited and transferred from Photosystem II (PS2). As these electrons are used up, they need to be replaced.

5. **Source of Replacement Electrons**: The splitting of water provides the necessary electrons to replace those lost from PS2. The chemical reaction can be summarized as:
\[ 2 \text{H}_2\text{O} \rightarrow 4 \text{H}^+ + \text{O}_2 + 4 \text{e}^- \]
This equation shows that two water molecules yield four protons, one oxygen molecule, and four electrons.

6. **Conclusion**: Since the splitting of water is responsible for providing electrons to replace those lost from Photosystem II during the light reactions, we conclude that the splitting of water molecules is associated with Photosystem II (PS2).

7. **Final Answer**: The correct answer is **B) Photosystem 2**.

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