Final answer:
Each pair of electrons transferred from NADH to oxygen via the electron-transport chain results in the formation of about three ATP molecules. FADH₂ yields fewer ATPs due to its entry point in the chain. Aerobic respiration produces a theoretical maximum of 38 ATPs from one glucose molecule.
Step-by-step explanation:
Each pair of electrons transferred from NADH to oxygen via the electron-transport chain releases enough energy to drive the formation of approximately three molecules of ATP. This is because the passage of electrons from one molecule of NADH through the electron transport chain generates a proton motive force that is utilized by the ATP synthase to synthesize ATP in a process known as oxidative phosphorylation.
The transfer of electrons from FADH₂ to oxygen results in the formation of only about two ATP molecules because electrons from FADH₂ enter the electron transport chain at a later point. This detail is important to the overall accounting of the number of ATP molecules produced during aerobic respiration as it can impact the final total yield of ATP.
Overall, from the complete oxidation of one molecule of glucose in aerobic respiration, a theoretical maximum yield of 38 ATP molecules can be produced. Still, typically a total of 36 ATPs are accounted for, reflecting the actual average yield.