Explain electron transport chain
Electron Transport Chain (ETC) – Simplified Explanation
The Electron Transport Chain (ETC) is the final stage of cellular respiration, occurring in the inner mitochondrial membrane . It is responsible for producing ATP, the energy currency of the cell.
Steps of ETC:
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Electron Donation: NADH and FADH2 (from glycolysis & Krebs cycle) donate electrons to the ETC.
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Electron Transfer: Electrons move through a series of protein complexes ( Complex I to IV ), releasing energy.
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Proton Pumping: This energy is used to pump H+ ions (protons) from the mitochondrial matrix to the intermembrane space, creating a proton gradient.
ATP Formation: Protons flow back into the matrix through ATP synthase , driving the formation of ATP from ADP + P.
Oxygen as Final Acceptor: At Complex IV , electrons combine with oxygen (O2) and protons to form water (H2O).
Conclusion:
The ETC produces around 34 ATP per glucose molecule, making it the most efficient energy-producing process in cells. Oxygen plays a vital role as the final electron acceptor.