How many ATP and NADPH molecuels are respectively required to mae one molecule of glucose through Calvin cycle?

Options

A. 3 and 2
B. 9 and 6
C. 18 and 12
D. 12 and 18

Explanation

To determine how many ATP and NADPH molecules are required to make one molecule of glucose through the Calvin cycle, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Calvin Cycle**:
- The Calvin cycle, also known as the C3 cycle, is the process by which plants convert carbon dioxide into glucose. It consists of three main stages: carboxylation, reduction, and regeneration.

2. **Identifying Energy Requirements for One CO2 Fixation**:
- For each carbon dioxide (CO2) molecule fixed, the cycle requires:
- **1 ATP** in the carboxylation phase.
- **1 ATP** and **2 NADPH** in the reduction phase.
- **1 ATP** in the regeneration phase.
- Therefore, the total energy required for fixing one CO2 molecule is:
- **Total ATP = 1 (carboxylation) + 1 (reduction) + 1 (regeneration) = 3 ATP**
- **Total NADPH = 2 NADPH (from the reduction phase)**

3. **Calculating for Glucose**:
- The molecular formula for glucose is C6H12O6, which indicates that it contains **6 carbon atoms**.
- To produce one molecule of glucose, the Calvin cycle must run **6 times** (once for each carbon atom).

4. **Total Energy Requirements for Glucose**:
- Since each cycle requires **3 ATP** and **2 NADPH** for one CO2, for 6 CO2 (to form one glucose), we multiply by 6:
- **Total ATP = 6 cycles × 3 ATP/cycle = 18 ATP**
- **Total NADPH = 6 cycles × 2 NADPH/cycle = 12 NADPH**

5. **Final Answer**:
- Therefore, to produce one molecule of glucose through the Calvin cycle, **18 ATP** and **12 NADPH** molecules are required.