In aerobic respiration, glucose is completely broken down into carbon dioxide and water. However, in anaerobic respiration, the breakdown of glucose is incomplete. The end product of anaerobic respiration is lactic acid instead of carbon dioxide and water. This process occurs in oxygen debt. Hence, the amount of oxygen required to oxidize lactic acid to carbon dioxide and water is not present. Aerobic respiration produces 38 ATP whereas anaerobic respiration produces only 2 ATP molecules.