Final answer:
Per molecule of glucose, two molecules of NADH are generated during pyruvate oxidation. This corresponds to one NADH per pyruvate molecule and since one molecule of glucose yields two pyruvate molecules, the total is two NADH molecules. The correct answer is option a. 2
Step-by-step explanation:
Per molecule of glucose, two molecules of NADH are generated by pyruvate oxidation. During glycolysis, glucose is first split into two molecules of pyruvate. This process yields a total of four ATP and two NADH molecules, but it's important to remember that to get the net gain, we must subtract the two ATP molecules that were consumed at the start of glycolysis, leaving a net gain of two ATP and two NADH. After glycolysis, each pyruvate molecule can be further oxidized in the presence of oxygen to yield additional energy carriers.
The question specifically asks about the production of NADH during pyruvate oxidation, which is a part of the aerobic respiration process that occurs after glycolysis. Here, each of the two pyruvate molecules (arising from one glucose molecule) is converted into an acetyl-CoA and one molecule of CO2. During this conversion, one NADH is produced per pyruvate. Thus, since we start with two pyruvate molecules from one glucose molecule, two NADH molecules are produced during this step.
Therefore, the correct answer is option (a) 2. Remember that the question refers to the step immediately following glycolysis, which is often termed as the link reaction or pyruvate decarboxylation, and not the entire cellular respiration process.