AP BIOLOGY

Detailed explanation-1: -It is a series of eight-step processes, where the acetyl group of acetyl-CoA is oxidised to form two molecules of CO2 and in the process, one ATP is produced. Reduced high energy compounds, NADH and FADH2 are also produced.

Detailed explanation-2: -Each acetyl CoA enters into citric acid cycle and yields 3 NADH2 (9 ATP), 1 FADH2 (2 ATP) and 1 GTP (1 ATP). Therefore, altogether 12 ATP molecules will be produced from each mole of acetyl-CoA.

Detailed explanation-3: -Since a single acetyl-CoA molecule fed into the citric acid cycle generates 3 NADH molecules, 1 FADH2 and 1 GTP, we see that a total of 24 NADH, 8 FADH2 and 8 GTP are produced when all 8 acetyl-CoA go into the citric acid cycle. This gives us a grand total of 31 NADH, 15 FADH2 and 8 GTP molecules.

Detailed explanation-4: -The Krebs cycle uses the two molecules of pyruvic acid formed in glycolysis and yields high-energy molecules of NADH and flavin adenine dinucleotide (FADH2), as well as some ATP. The Krebs cycle occurs in the mitochondrion of a cell (see Figure 6-1).

Detailed explanation-5: -NADH and FADH2 molecules formed during Glycolysis and Krebs Cycle carry their electrons to the electron transport chain. The electron transport chain creates a proton gradient that ultimately leads to the production of a large amount of ATP.