; The final product of the Calvin cycle … An enzyme, RuBisCO, catalyzes a reaction with CO 2 and another molecule, RuBP. Using the energy carriers formed in the first steps of photosynthesis, the light-independent reactions, or the Calvin cycle, take in CO 2 from the environment. The reactions of the Calvin cycle add carbon (from carbon dioxide in the atmosphere) to a simple five-carbon molecule called RuBP. The Calvin cycle is a set of light-independent chemical reactions, so you might also hear it referred to as the dark reactions. 3. Light-independent (“Dark”) Reactions. The cycle is light-independent because it takes place after the energy has been captured from sunlight.. This doesn't mean the Calvin cycle occurs only in the dark; it just doesn't require energy from light for the reactions to occur. This chemical reaction is sometimes known as the Calvin-Bensom-Bassham cycle, after Melvin Calvin, James Bassham, and Andrew Benson, the University of California researchers who first described the process. The Calvin cycle reactions use chemical energy from NADPH and ATP that were produced in the light reactions. The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into sugar, the food autotrophs need to grow. Summary of the “Light” Reactions. The final product of the Calvin cycle … Every living thing on Earth depends on the Calvin cycle. The reactions of the Calvin cycle add carbon (from carbon dioxide in the atmosphere) to a simple five-carbon molecule called RuBP. Calvin Cycle The second stage of photosynthesis, which takes place in the stroma of the chloroplast, can occur without the presence of sunlight. The Calvin cycle (also known as the Benson-Calvin cycle) is the set of chemical reactions that take place in chloroplasts during photosynthesis.. 5.3 The Calvin Cycle Using the energy carriers formed in the first stage of photosynthesis, the Calvin cycle reactions fix CO 2 from the environment to build carbohydrate molecules. As shown in Fig. The “Dark” Reactions A series of reactions called the Calvin cycle that synthesize glucose from CO 2 and H 2O: CO 2 + H 2O C 6 H 12 O 6 (glucose) ATP, NADPH After three cycles, a three-carbon molecule of G3P leaves the cycle to become part of a carbohydrate molecule. These reactions use chemical energy from NADPH and ATP that were produced in the light reactions. The Calvin cycle is named after Melvin C. Calvin, who won a Nobel Prize in Chemistry for finding it in 1961. Section Summary. Summary. Plants depend on the Calvin cycle for energy and food.Other organisms, including herbivores, also depend on it indirectly because they depend on plants for food. An enzyme, RuBisCO, catalyzes the fixation reaction, by combining CO 2 with RuBP. The Calvin cycle is a process in which stored energy is utilized to create usable compounds in a photosynthetic organism. In this stage, known as the Calvin Cycle, carbon molecules from CO2 are fixed into glucose (C6H12O2). It exists in plants and microalgae, as well as photoautotrophic and chemoautotrophic bacteria. w/ 3 turns of Calvin cycle, 3 CO2 enters, 3 RuBP regenerated, 1 glyceraldehyde 3-phosphate created uses enzymes that functions best under light glyceraldehydes 3-phosphate - 3-carbon sugar that can be converted to fructose 6-phosphate and glucose 1-phosphate in cytoplasm w/ … The reactions of the Calvin Cycle … The Calvin cycle, which is also called the reductive pentose phosphate cycle, is the most widespread CO 2 biofixation pathway among autotrophs.