What defines heterotrophic organisms?

Heterotrophic organisms are defined by their inability to synthesize their own food, which means they rely on other organisms, either plants or animals, for their nutritional needs. This characteristic distinguishes them from autotrophic organisms, which can produce their own food through processes like photosynthesis or chemosynthesis.

In the case of heterotrophs, they must obtain energy by consuming organic compounds. This could come from eating plants, animals, or decomposing organic material, depending on the specific type of heterotroph. This reliance on other forms of life for food underscores the diverse relationships in ecosystems, where energy and nutrients flow from producers to consumers.

The other choices describe different biological processes or characteristics but do not accurately define heterotrophic organisms. The photosynthesis mentioned in the first choice applies to autotrophs, while the third option incorrectly limits heterotrophs to only consuming plant material. Storing energy in the form of starch, as stated in the fourth choice, is also more characteristic of certain plants and is not a defining feature of all heterotrophs.