Why is aerobic respiration more effective than anaerobic respiration?
Actually, aerobic (cellular) respiration is more efficient than anaerobic, not more effective. Of course, what this means is that the breakdown of glucose in the presence of oxygen generates more usable energy for the cell than without. The reason is that each six carbon glucose molecule is left as two three-carbon lactic acid molecules instead of six carbon dioxides, and far fewer energy packets are generated (ATPs) – just two instead of 36 to 38 ATPs. In both pathways, the glucose molecule is converted to pyruvic acid (also called pyruvate), generating a net of 2 ATPs: Glucose + 2 NAD+ + 2 Pi + 2 ADP –> 2 pyruvate + 2 NADH + 2 ATP + 2 H2O Absent oxygen, pyruvate becomes lactate and can go no further. With oxygen, pyruvate is converted to acetyl-CoA instead of lactate, and enters the Krebs cycle (or citric acid cycle) and then the oxidative phosphorylation pathway where ultimately, only carbon dioxide and water are generatedalong with 36 to 38 ATPs – much more bang for the buck, and
