During Aerobic Respiration,electrons Travel Downhill in Which Sequence

Question

During aerobic respiration,electrons travel downhill in which sequence?
A)food → citric acid cycle → ATP → NAD⁺
B)food → NADH → electron transport chain → oxygen
C)glucose → pyruvate → ATP → oxygen
D)glucose → ATP → electron transport chain → NADH
E)food → glycolysis → citric acid cycle → NADH → ATP

Accepted Answer

During aerobic respiration, electrons are first extracted from food molecules and carried by NADH to the electron transport chain. The electron transport chain transfers the electrons to oxygen, which serves as the final electron acceptor. As the electrons pass through the electron transport chain, energy is released and used to pump protons across the inner mitochondrial membrane, creating an electrochemical gradient. This gradient drives the production of ATP via oxidative phosphorylation.