respiratory chain

A chain of organic molecules on the inner surface of mitochondria capable of accepting hydrogen atoms and electrons derived from the Krebs cycle during aerobic metabolism. The hydrogen atoms, and then the electrons, are transferred in an ordered sequence along the chain by a series of redox reactions; the final reaction involves the reduction of oxygen to form water. The redox reactions liberate free energy, which is used to manufacture ATP; this metabolic process is known as oxidative phosphorylation.

Respiratory chain
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