A series of enzymes and proteins in living cells through which electrons are transferred, via a series of oxidation-reduction reactions. This ultimately leads to the conversion of chemical energy into a readily usable and storable form. The most important electron transport chain is the respiratory chain, present in mitochondria and functioning in cellular respiration.
The stage of cellular respiration in which the most adenosine triphosphate is generated. In this crucial biochemical reaction, electrons are passed along a cell or mitochondrial membrane and ultimately accepted by oxygen, producing water. Hydrogen ions (protons) are transported across the membrane. The source of the protons and electrons is primarily nicotinamide adenine dinucleotide, which is recycled during the reaction.