Question

what is the main transformation that occurs during glycolysis?
glycolysis produces atp and pyruvate by oxidizing water.
glycolysis produces atp and pyruvate by oxidizing glucose and nad+
glycolysis produces pyruvate, atp, and nadh by oxidizing glucose.
glycolysis produces co₂, atp, and pyruvate by reducing glucose.

Explanation:

Glycolysis is the first step of cellular respiration. In glycolysis, one molecule of glucose (a 6 - carbon sugar) is oxidized. During this process, 2 molecules of ATP are used initially (from 2 ATP to 2 ADP), but 4 molecules of ATP are produced (from 4 ADP to 4 ATP), resulting in a net gain of 2 ATP. Also, 2 molecules of \(NAD^{+}\) are reduced to 2 molecules of NADH. And the end - product is 2 molecules of pyruvic acid (a 3 - carbon compound).

• Option 1: Glycolysis does not oxidize water.
• Option 2: While glucose is oxidized, \(NAD^{+}\) is reduced (not oxidized) in glycolysis.
• Option 3: This option correctly states that glucose is oxidized, and the products are pyruvate, ATP, and NADH.
• Option 4: Glycolysis does not produce \(CO_{2}\), and glucose is oxidized (not reduced) in glycolysis.

Answer:

Glycolysis produces pyruvate, ATP, and NADH by oxidizing glucose.