Decomposers are the organisms that break down organic material such as the remains of dead organisms (plants and animals). Bacteria and fungi are decomposers. Their main function is to carry out a constant circulation of organic matter in the ecosystem. Decomposers are heterotrophic, which get their energy from the dead organism. They provide nutrients for decomposers to grow and reproduce, propagating their species. After decomposers break down dead organisms, organic matter passes into the circulating system whereas the decomposers are destroyed by environmental conditions or are consumed by other organisms.