In biology, carbon fixation is the reduction of inorganic carbon (carbon dioxide) to organic compounds by living organisms. The most prominent example is photosynthesis. Organisms that grow by fixing carbon are called autotrophs—plants for example. Heterotrophs, like animals, are organisms that grow using the carbon fixed by autotrophs. Fixed carbon, reduced carbon, and organic carbon all mean organic compounds.
Read more about Carbon Fixation: Fossil Carbon, Other Autotrophic Pathways, Non-autotrophic Pathways, Carbon Isotope Discrimination, Other Reduced Carbon