A native tale All energy used by organisms comes from the sun. Organisms that can get this energy directly from sunlight are called autotrophs. Most autotrophs are green plants, which use the suns energy to combine carbon dioxide from the atmosphere with water to form carbohydrate by photosynthesis .
Autotrophs are producers.
Most plants and some bacteria are autotrophs. Heterotrophs are organisms that are unable to use energy directly from the sun. They must get their food by eating autotrophs or other heterotrophs. Heterotrophs are consumers and decomposers. Heterotrophs are consumers and decomposers.