The dark processes, a complicated series of enzymatically controlled chemical reactions, are what turn carbon into organic molecules. This word is rather misleading because these responses can occur in both light and darkness. As a result of extended darkness, some of the enzymes involved in the so-called dark processes become dormant; nevertheless, when the leaves that contain them are exposed to light, they become active.
The synthesis of intermediate sugar phosphates occurs in a cyclic process during the Calvin-Benson cycle, which involves the fixation, reduction, and use of carbon. Three molecules of carbon dioxide are used in a full cycle, which results in the production of one molecule of the three-carbon chemical glyceraldehyde-3-phosphate (Gal3P). Typically, the chloroplasts either export this three-carbon sugar phosphate or convert it to starch the chloroplast's inside.
The process of adding carbon dioxide to the five-carbon compound ribulose 1,5-bisphosphate (RuBP) and splitting the resulting six-carbon compound into two molecules of PGA is known as the initial incorporation of carbon dioxide, which is catalyzed by the enzyme ribulose 1,5-bisphosphate carboxylase (Rubisco). Each full turn of the cycle sees this reaction take place three times, resulting in the production of six PGA molecules.