The maximum ATP is made in a cell under aerobic conditions. In aerobic respiration, a total of 38 ATP molecules are made from every molecule of glucose, whereas in anaerobic respiration, only 2 ATP molecules are generated.
Aerobic respiration is therefore 19 times more effective at releasing energy than anaerobic respiration because aerobic processes extract most of the glucose molecule's energy in the form of ATP , while anaerobic processes leave most of the ATP generating sources in the waste products.