A European Informational Website
learn more
An electron transport chain (also called electron transport system (ETS) or electron transfer chain (ETC)) is a series of membrane-associated electron carriers mediating biochemical reactions that produce adenosine triphosphate (ATP), which is the energy currency of life. Only two sources of energy are available to living organisms: oxidation-reduction (redox) reactions and sunlight (photosynthesis). Organisms that use redox reactions to produce ATP are called chemotrophs. Organisms that use sunlight are called phototrophs. Both chemotrophs and phototrophs utilize electron transport chains to convert energy into ATP.