Question

How do chemoautotrophs make energy?

Answer 1

autotrophs=self feeding, they synthesize compounds from carbon dioxide

Answer 2

Chemoautotrophs (or chemotrophic autotroph), in addition to deriving energy from chemical reactions, synthesize all necessary organic compounds from carbon dioxide. Chemoautotrophs generally only use inorganic energy sources. Most are bacteria or archaea that live in hostile environments such as deep sea vents and are the primary producers in such ecosystems. Evolutionary scientists believe that the first organisms to inhabit Earth were chemoautotrophs that produced oxygen as a by-product and later evolved into both aerobic, animal-like organisms and photosynthetic, plant-like organisms. Chemoautotrophs generally fall into several groups: methanogens, halophiles, sulfur reducers, nitrifiers, anammoxbacteria and thermoacidophiles.