Complex I (NADH dehydrogenase):
This complex receives electrons from NADH and transfers them to ubiquinone (Q).
Complex II (Succinate dehydrogenase):
This complex receives electrons from succinate (FADH2) and transfers them to ubiquinone (Q).
Complex III (Cytochrome reductase or Q-cytochrome c oxidoreductase):
This complex accepts electrons from ubiquinol (QH2) and transfers them to cytochrome c.
Complex IV (Cytochrome oxidase or cytochrome c oxidase):
This complex receives electrons from cytochrome c and transfers them to oxygen, forming water.
Complex V (ATP synthase):
While not directly part of the electron transport chain itself, ATP synthase utilizes the proton gradient generated by the electron transport chain to produce ATP.
