AP BIOLOGY

Detailed explanation-1: -Let’s look back at our question about the number of turns of the Krebs cycle for each molecule of glucose. Because there’s two pyruvates formed after glycolysis, there will be two acetyl-CoA molecules formed, and therefore two rounds of the Krebs cycle. So the correct answer choice is (B), two turns.

Detailed explanation-2: -For one glucose molecules, there will be two rounds of Krebs cycle. This is because two molecules of Pyruvic acid are formed from one molecule of glucose during Glycolysis.

Detailed explanation-3: -Two molecules of acetyl-CoA are produced from each glucose molecule so two turns of the Krebs cycle are required which yields four CO2, six NADH, two FADH2 and two ATPs.

Detailed explanation-4: -Results of the Krebs Cycle After the second turn through the Krebs cycle, the original glucose molecule has been broken down completely. All six of its carbon atoms have combined with oxygen to form carbon dioxide.

Detailed explanation-5: -In the Krebs cycle, two ATP, six NADH +H+, and two FADH2 were produced. A net of four ATPs was produced from glycolysis through the Krebs cycle. More ATP will be produced from reduced coenzymes in the mitochondria during the electron transport chain and oxidative phosphorylation.