Best defined function of Maganese in green plants is

Options

A. Calvin cycle
B. Nitrogen fixation
C. Water absorption
D. Photolysis of water

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of Manganese in Plants:**
- Manganese is an essential micronutrient for plants and plays a crucial role in various physiological processes.

2. **Photosynthesis Overview:**
- Photosynthesis is the process by which green plants convert light energy into chemical energy, primarily occurring in the chloroplasts.

3. **Light Reaction of Photosynthesis:**
- The process of photosynthesis consists of two main stages: light reactions and the Calvin cycle. The light reactions occur in the thylakoid membranes of the chloroplasts.

4. **Photolysis of Water:**
- During the light reactions, water molecules are split into hydrogen ions and oxygen. This process is known as photolysis.

5. **Manganese's Involvement in Photolysis:**
- Manganese is specifically involved in the photolysis of water, as it is a cofactor for the enzyme that facilitates this reaction. It helps in the splitting of water molecules, which is essential for the production of oxygen and the transfer of electrons in the photosynthetic process.

6. **Evaluating the Options:**
- Given the options: Calvin cycle, nitrogen fixation, water absorption, and photolysis of water, we can eliminate Calvin cycle and nitrogen fixation as they do not directly involve manganese.
- Water absorption is a general process and does not specifically relate to manganese's role.
- Therefore, the best-defined function of manganese in green plants is its role in the photolysis of water during photosynthesis.

**Final Answer:**
The best-defined function of manganese in green plants is the photolysis of water.

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