Answer:
Electron transport chain (ETC)
Step-by-step explanation:
NADH is a reducing power. During the oxidative breakdown of glucose by glycolysis and Kreb's cycle, some of the electrons and hydrogen ions are accepted by NAD+. In these reactions, NAD+ molecules become reduced into NADH. NADH molecules serve as temporary energy storage and deliver the electrons and hydrogen ions to the proteins of the electron transport chain. The electron transport chain makes the final stage of cellular respiration during which NADH and FADH2 are oxidized by delivering their electrons and hydrogen ions to the proteins of the chain.