The net gain of ATP molecules from the complete aerobic respiration of one molecule of glucose is

The complete aerobic respiration of one glucose molecule yields a net gain of approximately 38 ATP molecules. This includes 2 ATP from glycolysis, 2 ATP from the Krebs cycle, and 34 ATP from oxidative phosphorylation in the electron transport chain. Some sources cite 36 ATP due to the energy cost of transporting NADH across the mitochondrial membrane, but 38 is the accepted value in most WAEC syllabi.