During cellular respiration the electron transport system is responsible for producing most ATP. The electron transport chain of the cellular respiration process produces maximum ATP. There are three parts of cellular respiration; Glycolysis which produces 2 ATP; krebs cycle which does not produce any ATP, but produces electron carriers that are used in the production of ATP, lastly, the oxidatiCe phsophoylation, which involves the electron transport chain that produces maximum ATP. It takes one NADH molecule to produce 2.5 ATP and one FADH2 via channel 2 to produce 1.5 ATP, to yield a total of 34 ATP.