Synthesis of one glucose molecule requires- reduced NADP molecules

Options

A. 6
B. 12
C. 18
D. 24

Answer

To determine how many reduced NADP molecules (NADPH) are required for the synthesis of one glucose molecule, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Calvin Cycle**:
- The Calvin Cycle is the process through which carbon dioxide (CO2) is fixed into organic molecules. It involves several turns of the cycle to produce glucose.

2. **Carbon Dioxide Requirement**:
- For every 3 molecules of CO2 that enter the Calvin Cycle, one molecule of glyceraldehyde-3-phosphate (G3P), a 3-carbon compound, is produced.

3. **G3P to Glucose Conversion**:
- To form one glucose molecule (which is a 6-carbon compound), two molecules of G3P are required. Therefore, to produce 2 G3P, the Calvin Cycle must complete 6 turns (since 6 turns will fix 18 carbon atoms, yielding 6 G3P).

4. **ATP and NADPH Requirement per Turn**:
- Each turn of the Calvin Cycle requires:
- 3 molecules of ATP
- 2 molecules of NADPH

5. **Calculating Total for 6 Turns**:
- For 6 turns of the Calvin Cycle:
- **ATP**: 3 ATP/turn × 6 turns = 18 ATP
- **NADPH**: 2 NADPH/turn × 6 turns = 12 NADPH

6. **Conclusion**:
- Therefore, the synthesis of one glucose molecule requires a total of 12 reduced NADP molecules (NADPH).

### Final Answer:
The synthesis of one glucose molecule requires **12 reduced NADP molecules (NADPH)**.

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