Which one of the following is not involved in photolysis of water?

Options

A. Mn
B. Mg
C. CI
D. Ca

Answer

**Step-by-Step Solution:**

1. **Understanding Photolysis of Water**:
- Photolysis refers to the process of breaking down water molecules using light energy. The term "photo" means light, and "lysis" means breakdown. This process is essential in photosynthesis.

2. **Location of Photolysis**:
- Photolysis of water occurs in the thylakoid lumen of chloroplasts during the light-dependent reactions of photosynthesis.

3. **Elements Involved in Photolysis**:
- The key elements required for the photolysis of water are manganese (Mn), chlorine (Cl), and calcium (Ca). These elements play crucial roles in the process.

4. **Identifying the Incorrect Element**:
- The question asks for the element that is not involved in the photolysis of water. Among the options given, magnesium (Mg) is not required for this specific process.

5. **Conclusion**:
- Therefore, the correct answer to the question "Which one of the following is not involved in photolysis of water?" is magnesium (Mg).

**Final Answer**: Magnesium (Mg) is not involved in the photolysis of water.

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