An organism that obtains organic food molecules by eating other organisms or their by-products

heterotrophs

Explanation:

According to the parameters established by biology, all living beings that require others to feed themselves are considered heterotrophs, that is, they are not able to produce their food within their organism but rather they must consume elements of nature already constituted as food, already synthesized by other organisms. Among the most prominent heterotrophs, all animals, bacteria and humans stand out.

The term heterotroph comes from the Greek, language in which the prefix hetero means different and trophies means food. In this way, the heterotroph is one that feeds on elements other than one, which takes elements from nature, from the surrounding space to feed. While autotrophic beings have the ability to synthesize inorganic elements such as light, water, carbon dioxide and convert them into food; Heterotrophic beings do not have that capacity, so they must consume plants (in the case that they are herbivores) or animals that have already consumed those plants (that is, in the case that they are carnivorous). In other words, animals and humans always need to feed on other living beings, they could never do so only from inorganic elements such as water.