Evolution of photosynthesis symbiotic relationship with chloroplasts they capture from the algae in their diet and then store in their bodies. This allows the mollusks to survive solely by photosynthesis for several months at a time. Some of the genes from the plant cell nucleus have even been transferred to the slugs, so that the chloroplasts can be supplied with proteins that they need to survive. An even closer form of symbiosis may explain the origin of chloroplasts. Chloroplasts have many similarities with photosynthetic bacteria, including a circular chromosome, prokaryotic-type ribosomes, and similar proteins in the photosynthetic reaction center. The endosymbiotic theory suggests
Fractionation of carbon isotopes in oxygenic photosynthesis + 2 H + 3 ATP + OThe light-independent reactions undergo the Calvin-Benson cycle, in which the energy from NADPH and ATP is used to convert carbon dioxide and water into organic compounds via the enzyme RuBisCO. The overall general equation for the light-independent reactions is the following:3 CO + 9 ATP + 6 NADPH + 6 H → CHO-phosphate + 9 ADP + 8 P + 6 NADP + 3 HOThe 3-carbon products (CHO-phosphate) of the Calvin cycle are later converted to glucose or other carbohydrates such as starch, sucrose, and cellulose. The large fractionation of C in photosynthesis