Here's why:

* Heterotroph: The word "hetero" means "other" and "troph" means "nourishment". So, heterotrophs obtain their nourishment from other organisms. They consume organic matter (plants, animals, or decaying matter) to get the energy and nutrients they need.

* Autotroph: In contrast, organisms that make their own food through processes like photosynthesis (like plants) are called autotrophs.