Number of NADH produced during breakdown of one molecule of glucose to 1 : 3 diphosphoglycerate stage is

Options

A. 6
B. 4
C. 3
D. 2

Answer

To determine the number of NADH molecules produced during the breakdown of one molecule of glucose to the 1,3-diphosphoglycerate stage, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Glycolysis**: Glycolysis is the metabolic pathway that converts glucose into pyruvate, producing ATP and NADH in the process. It consists of 10 enzymatic reactions.

2. **Identifying the Relevant Stage**: The question specifically asks about the production of NADH up to the 1,3-diphosphoglycerate stage. This is the sixth step of glycolysis.

3. **Examining the Reactions**: In glycolysis, NADH is produced during the conversion of glyceraldehyde 3-phosphate (G3P) to 1,3-diphosphoglycerate (1,3-DPG). This reaction is catalyzed by the enzyme glyceraldehyde 3-phosphate dehydrogenase.

4. **Calculating NADH Production**: During this specific reaction, two molecules of NAD+ are reduced to form two molecules of NADH. Therefore, for one molecule of glucose, which produces two molecules of glyceraldehyde 3-phosphate, two NADH molecules are generated.

5. **Conclusion**: Thus, the total number of NADH produced during the breakdown of one molecule of glucose to the 1,3-diphosphoglycerate stage is **2**.

### Final Answer:
The number of NADH produced during the breakdown of one molecule of glucose to the 1,3-diphosphoglycerate stage is **2**.

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