Heterotrophs, which are all animals, all fungi, most bacteria and some protoctists, obtain their energy as 'ready made' organic matter by ingesting material from other organisms. Some of the energy fixed within organic molecules bu autotrophs (aka producers) is transferred to other organisms in the ecosystem.
Heterotrophs cannot make their own food, instead they must consume it. All heterotrophs are consumers and depend on producers for their food.
- Primary consumers, aka herbivores, are heterotrophs that eat plant material.
- Secondary consumers, aka carnivores, feed on primary consumers.
- Tertiary consumers, also carnivores, eat other consumers. The carnivores at the top of the food chain are sometimes called top carnivores.
- Animals that kill and eat other animals are called predators and carnivores.
- Animals that eat plants and other animals are known as omnivores.
Enery is transferred from producers to primary consumers, then to secondary consumers, then sometimes to tertiary consumers. These feeding reletionships can be seen in a food chain. The position a species occupies in a food chain is called a trophic level.
Energy is transferred from one trophic level to the next trophic level by consumers.
microscopic algae --->…