A reaction pathway known as the Calvin or Calvin-Benson Cycle and is like the Krebs Cycle because by the end of each turn of the cycle, the starting compound has been regenerated. It is a food and forms in the grana. PGAL is also usable directly as a building material and can form chlorophyll, NADP, or Ribulose 5-P or any of the enzymes taking part in carbon dioxide fixation. More PGAL is usually manufactured than needed - the bulk is available for export to nonphotosynthesizing cells of the plant. PGAL is too reactive to be exported as such but is transformed into sugars such as sucrose, glucose, or fructose.
Sugar is often the primary endproducts of photosynthesis.
Storage occurs primarily in roots and stems, some in leaves. The larger the storage unit, starches for example, the smaller it is in terms of individual units because of the water loss during dehydration synthesis. Plant that use ONLY the Calvin-Benson Cycle are known as C 3 plants. It involves the oxidation of carbohydrates but no yield of ATP or NADH 2 . This reduces the efficiency of C 3 carbon dioxide fixation.