Cellular respiration is the process by which organisms use oxygen to break down food molecules to get chemical energy for cell functions.
Krebs Cycle: the sequence of reactions by which most living cells generate energy during the process of cellular respiration. It takes place in the mitochondria, consuming oxygen, producing carbon dioxide and water as waste products, and converting ADP to energy-rich ATP.
Electron carriers are reduced during glycolysis and Krebs cycle to NADH + H+ and FADH2. These carriers then donate electrons and protons to the electron carrier proteins of the electron transport chain. The final electron acceptor is oxygen. Together with oxygen, electrons and protons form molecules of water.
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