heterotrofit

Heterotroph, sometimes written as heterotrofit in some languages or contexts, is a biological nutritional mode describing organisms that cannot synthesize all essential organic compounds from inorganic sources. Instead, they obtain carbon and energy by consuming preformed organic matter produced by other organisms.

In contrast to autotrophs, which fix carbon dioxide to form organic compounds, heterotrophs rely on existing organic molecules for both carbon and energy, although some use light as an energy source (photoheterotrophs).

Two broad subcategories are chemoheterotrophs and photoheterotrophs. Chemoheterotrophs derive energy from chemical bonds in organic compounds and obtain carbon from the same molecules, while photoheterotrophs use light for energy but rely on organic carbon.

Heterotrophs include animals, fungi, and many bacteria, as well as some protists. They occupy diverse ecological roles as consumers, decomposers, parasites, and symbionts, and they drive nutrient cycling by breaking down complex organic matter into simpler compounds.

Metabolic processes commonly used by heterotrophs include respiration (aerobic and anaerobic) and fermentation, enabling the release of energy from organic substrates. Mixotrophy also occurs, where an organism combines heterotrophic nutrition with autotrophic or phototrophic modes.