There are three types of symbiotic relationships that you will study in more detail later. Mutualism where both organisms benefit, commensalism where one organism benefits, and parasitism where the host may be killed by the parasite. The producers make their own food. Consumers eat the foods produced and decomposers recycle nutrients back into the ecosystem. In every ecosystem , there is a pathway of energy flow that always begins with the producers.
Producers make organic nutrients which are transferred to consumers when the plants are eaten.
Herbivores which eat plants are first level consumers. Carnivores that eat the plant eating animals are second level consumers. Many consumers have a varied diet and fit in several places in the food chain. This food chain is a series of organisms through which food energy is passed. Many food chains are interconnected at various points so food webs are formed.