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Cellular Respiration
The electron transport chain

Home | Key Terms/ Key Words | What happens before cellular respiration? | Glycolysis | Transition Reactions | Kreb's Cycle | The electron transport chain | Fermentation

The Fourth and Final Phase of Cellular Respiration

As NADH and FADH2 enter the electron transport chain, their electrons and hydrogen ions are transported to the cristae. The proteins and enzymes in the electron transport chain oxidize NADH and FADH2. You are now left with NAD and FAD. The NAD and FAD return to the reactions in the matrix (glycolysis,krebs cycle, etc.) and their hydrogen ions are pumped across the internal membrane and into the intermediate space. As they are pumped across the chain, they begin to lose energy and once they've lost it they have to be removed. The hydrogen ions are then pumped through ATP synthase and ATP is synthesized. 32 ATP molecules are produced in this stage.