From where organisms get energy and nutrients: Consumers

Many bacteria, animals and human beings eat various kinds of plants or animals to get energy and nutrients. They are called consumers since they consume the body or body part of other organisms.

Consumers cannot use abiotic factors directly as food. All organisms that depend on other living organisms for getting energy and nourishment are known as Heterotrophs (hetero = others, troph = nourishment). Some of them use only plants as the food materials (Herbivores) while others eat other animals (Carnivore). In many ecosystems, you could see animals, which consume both plant materials as well as animals (Omnivores). 

 

Below are videos of consumers living in aquatic ecosystems, observe them carefully