One of the similarities between aerobic and anaerobic respiration is that they both use glucose as the initial molecule, which is called the substrate. Moreover, both aerobic and anaerobic respiration produce Adenosine 5'-triphosphate (ATP), however, aerobic respiration produces more ATP compared to anaerobic respiration. Which actually means that glucose goes through dissimilar processes in anaerobic and aerobic respiration, therefore producing a different amount of ATP. Aerobic respiration uses oxygen and is only done when there is an abundant supply of oxygen. On the contrary, anaerobic respiration does not use oxygen, therefore it can be used even with a small supply of oxygen, hence we can still produce some ATP, for example when doing a strenuous exercise. Additionally, the products of both reactions are not the same. Aerobic respiration produces water and carbon dioxide from the reaction. On the other hand, anaerobic respiration produces lactic acid only, that can be harmful in large amounts, that is why it has to go to the liver once it has been produced so that it will be broken down.
