Carbon fixation, which is also referred to as carbon assimilation, is a process in which carbon dioxide is converted to an organic compound by a living organism. An example of carbon fixation is photosynthesis.
In the process of photosynthesis, the carbon is fixed from an inorganic form (carbon dioxide) into an organic form. This occurs as plants use energy from the sun to turn carbon dioxide and water into glucose (organic form). In photosynthesis, the carbon dioxide enters the leaves of plants and then diffuses into the mesophyll cells. The carbon then diffuses into the stroma of the chloroplasts, and this is where the light reaction of photosynthesis takes place. Carbon fixation is the first stage in the Calvin Cycle of fixation, reduction and regeneration.