The purpose of the Electron Transport Chain is to receive the high energy electrons carried by the coenzymes NADH &FADH2 and use the energy from these electrons to pump protons out of the matrix. A high concentration of protons results. As the protons diffuse back to the matrix, their energy is used by the ATP synthase to create 32 ATP.

Oxidative phosphorylation (electron transport) - The creation of ATP via chemiosmosis as a result of electron transport.

a) Occurs at cristae (Inner membranes)

b) NADH & FADH2 deliver H+ and e- to cristae.

c) Electrons "transport" along cristae through electron acceptors, provide energy to pump H+ from matrix to outer compartment.

d) Concentration of H+ is now higher in outer compartment. H+ pass through ATP synthases in cristae back to matrix. 32 ATP are made. This is known as chemiosmosis.

e) Last step involves H+ & e- added to oxygen. This frees NAD+ to return to glycolysis & Krebs Cycle to pick up more H+ & e-.

 

[Diagram of Electron Transport] -- [Release of Energy by Electrons During Electron Transport] -- [Diagram of Chemisosmosis]

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