Q46 / 200 · MHT CET - Medical 2026 (24 April Shift 2) · Biology
During lactic acid fermentation, pyruvic acid is reduced to lactic acid using one proton and two electrons from ________________.
- Correct answerA$\text{NADH} + \text{H}^+$ produced during glycolysis.
- B$\text{FADH}_2$ produced in Krebs cycle.
- CAcetyl CoA.
- DWater.
Solution
During lactic acid fermentation, pyruvic acid is reduced to lactic acid by the enzyme lactate dehydrogenase.
The reducing agent for this reaction is $\text{NADH} + \text{H}^+$, which is produced during the oxidation steps of glycolysis.
In this process, $\text{NADH} + \text{H}^+$ donates electrons and a proton to pyruvic acid, getting reoxidized to $\text{NAD}^+$, which is then reused in glycolysis.
Answer: $\text{NADH} + \text{H}^+$ produced during glycolysis.
The reducing agent for this reaction is $\text{NADH} + \text{H}^+$, which is produced during the oxidation steps of glycolysis.
In this process, $\text{NADH} + \text{H}^+$ donates electrons and a proton to pyruvic acid, getting reoxidized to $\text{NAD}^+$, which is then reused in glycolysis.
Answer: $\text{NADH} + \text{H}^+$ produced during glycolysis.
Hence, the correct answer is option: 'A'.