Reducing agents are required:
- in connection with the building metabolism for syntheses of endogenous substances,
- in connection with the energy metabolism of chemotrophic organisms for energy-supplying redox reactions .
The adjective for "organotrophy" is "organotrophic" (organotrophic living beings, organotrophic metabolism ).
If the energy requirement of organotrophic creatures is covered by exergonic metabolism ( chemotrophy ), this is called chemoorganotrophy , if it is covered by light ( phototrophy ), it is called photoorganotrophy .
Example of photoorganotrophic organisms: the bacterium Rhodospirillum
As a rule, organotrophic creatures use organic substances not only as reducing agents, but also as starting materials for the construction of the body's own substances, whereby less energy is required than when using inorganic building material sources. The use of organic materials as building material sources is called heterotrophy .