Solution:

Consumers are organisms that eat organisms from a different population. These organisms are formally referred to as heterotrophs, which include animals, some bacteria and fungi. Such organisms may consume by various means, they are called primary consumers.

Within an ecological food chain, Consumers are categorized into primary consumers, secondary consumers, and tertiary consumers. Primary consumers are herbivores, feeding on plants. Secondary consumers, on the other hand, are carnivores and prey on other animals. Omnivores, who feed on both plants and animals, can also be considered a secondary consumer.

Tertiary consumers, sometimes also known as apex predators, are usually at the top of food chains, capable of feeding on secondary consumers and primary consumers. Tertiary consumers can be either fully carnivorous or omnivorous.