Ecology
Autotroph
From Greek 'auto' (self) + 'trophe' (nourishment)
An organism that produces its own food from inorganic substances, typically through photosynthesis or chemosynthesis. The foundation of nearly all food webs.
Biological Context
Plants, algae, and some bacteria are autotrophs. They capture energy from sunlight (photoautotrophs) or chemical reactions (chemoautotrophs) and convert carbon dioxide into organic compounds. Without autotrophs, ecosystems would have no energy source.