Heterotrophs obtain their carbon atoms from organic compounds. Most prokaryotes are heterotrophs. Heterotrophs are organisms that get the carbon necessary for life from organic substrates. They cannot synthesize organic carbon-based compounds from inorganic sources in the environment like an autotroph can. Heterotrophs are known as consumers in the food chain. They can feed on autotrophs, heterotrophs, or sometimes their own waste products. More simply, a heterotroph might eat plants or another animal to get necessary carbon to sustain its own life. Most bacteria and all animal and fungal species are heterotrophic.