Organisms that must obtain nutrients and energy by eating other organisms are called heterotrophs.

Here's why:

* Hetero- means "other"

* -troph means "nourishment"

So, heterotrophs literally mean "other nourishment," indicating that they rely on consuming other organisms for their nutritional needs.

Here are some examples of heterotrophs:

* Animals: All animals are heterotrophs. They eat plants, other animals, or both.

* Fungi: Fungi get their nutrients by decomposing dead organisms.

* Many bacteria: Some bacteria are heterotrophic, consuming other microorganisms or organic matter.

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