In green plants photosynthesis what is the hydrogen donor and gets oxidised to `O_(2)`?

Options

A. `H_(2)O`
B. `CO_(2)`
C. Glucose
D. `H_(2)S`

Answer

**Step-by-Step Solution:**

1. **Understanding Photosynthesis**: Photosynthesis is the process by which green plants convert light energy into chemical energy, producing glucose and oxygen from carbon dioxide and water.

2. **Identifying the Components**: In photosynthesis, the main components involved are:
- Water (H2O)
- Carbon Dioxide (CO2)
- Glucose (C6H12O6)
- Oxygen (O2)

3. **Role of Water**: During the light reactions of photosynthesis, water is split (a process known as photolysis) to provide electrons, protons (hydrogen ions), and oxygen.

4. **Hydrogen Donor**: In the context of the question, the hydrogen donor is the substance that provides hydrogen ions (H+) during the photosynthesis process. Here, water (H2O) acts as the hydrogen donor.

5. **Oxidation to Oxygen**: When water is split, it is oxidized, resulting in the release of oxygen gas (O2) as a byproduct. This process occurs in Photosystem II, one of the two photosystems involved in the light-dependent reactions.

6. **Conclusion**: Therefore, in green plants during photosynthesis, the hydrogen donor that gets oxidized to oxygen is water (H2O).

**Final Answer**: The hydrogen donor that gets oxidized to O2 in green plants during photosynthesis is **water (H2O)**.

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