An autotroph ("sel-feedin", frae the Greek autos "sel" an trophe "nourishin") or producer, is an organism that produces complex organic compoonds (sic as carbohydrates, fats, an proteins) frae semple substances present in its surroondins, generally uisin energy frae licht (photosynthesis) or inorganic chemical reactions (chemosynthesis).[1]

Owerview o cycle atween autotrophs an heterotrophs. Photosynthesis is the main means bi that plants, algae an mony bacteria produce organic compoonds an oxygen frae carbon dioxide an watter (green arrow).


  1. Chang, Kenneth (12 September 2016). "Visions of Life on Mars in Earth's Depths". New York Times. Retrieved 12 September 2016.