Producers: Producers manufacture foods by converting sunlight to energy in the process of photosynthesis. One good example is the chlorophyll-bearing plants and photosynthetic bacteria. But some producers manufacture food without the aid of sunlight by just using chemical energy of simple inorganic substances like mushrooms

Consumers: This is mostly composed of herbivores, carnivores and omnivores. Macroconsumers are large consumers like animals depends food on other organism. Hence, macroconsumers like decomposers may also described as heterotrophic. The hetero which means other because the term describe organisms the feed on others, macroconsumers are grouped into three according to their food preferences.

Decomposers: Decomposers refer to small consumers like bacteria, fungi and worms that cause the decay of dead organism. They are sometimes called to as microconsumer because many of them are microorganisms that are too small to be seen by the naked eye.