Best defined function of manganese 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:**
- Manganese is classified as a micronutrient essential for plant growth and development. Micronutrients are required in smaller quantities compared to macronutrients.

2. **Identifying Functions of Manganese:**
- Manganese plays several roles in plants, but we need to identify the best-defined function among the options given: Kelvin cycle, nitrogen fixation, water absorption, and photolysis of water.

3. **Analyzing the Options:**
- **Kelvin Cycle:** This is primarily associated with carbon fixation in photosynthesis, not specifically linked to manganese.
- **Nitrogen Fixation:** This process involves converting atmospheric nitrogen into a usable form for plants, which is not a primary function of manganese.
- **Water Absorption:** While manganese may play a role in overall plant health, it is not directly responsible for water absorption.
- **Photolysis of Water:** This is the process of breaking down water molecules using light energy, which is essential in photosynthesis. Manganese acts as a cofactor in this process.

4. **Conclusion:**
- The best-defined function of manganese in green plants is the photolysis of water, where it facilitates the breakdown of water molecules during photosynthesis.

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

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