Two main characteristics that distinguish autotrophs from heterotrophs are:
A~ Autotrophs produce their own food by either chemosynthesis or photosynthesis. Heterotrophs do not produce their own food. Heterotrophs obtain their food by consuming autotrophs or heterotrophs.
B~ Autotrophs are at the primary level in a food chain and Heterotrophs are at the secondary level or tertiary level in a food chain.
