Hydrogen for the synthesis of organic compounds in photosynthesis comes from

Options

A. `NADH_(2)`
B. `FADH_(2)O`
C. `H_(2)O`
D. `CO_(2)`

Answer

To solve the question "Hydrogen for the synthesis of organic compounds in photosynthesis comes from," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Photosynthesis**:
- Photosynthesis is the process by which plants synthesize organic compounds, primarily glucose, using carbon dioxide (CO2) and water (H2O) in the presence of sunlight.

2. **Identifying the Sources of Hydrogen**:
- In photosynthesis, hydrogen is a crucial element that combines with carbon to form organic compounds.

3. **Analyzing the Options**:
- The options provided are:
- A) NADH2
- B) FADH2
- C) H2O
- D) CO2

4. **Evaluating Each Option**:
- **NADH2 and FADH2**: These are electron carriers involved in cellular respiration and do not directly provide hydrogen for the synthesis of organic compounds in photosynthesis.
- **CO2**: While carbon dioxide provides carbon for the synthesis of glucose, it does not provide hydrogen.
- **H2O**: Water is split during the process of photosynthesis, specifically during the light-dependent reactions. This process, known as photolysis, breaks down water into hydrogen (H2) and oxygen (O2).

5. **Conclusion**:
- Since hydrogen for the synthesis of organic compounds in photosynthesis comes from the splitting of water, the correct answer is **C) H2O**.

### Final Answer:
Hydrogen for the synthesis of organic compounds in photosynthesis comes from **H2O** (water).

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