calvin cycle - ib bio

step one - carbon fixation

two CO₂ molecules are attached to 2 five-carbon ribulose biphosphates (RuBP) by rubisco, an enzyme, this creates 6 glycerate-3-phosphate, which are three-carbon molecules.

step two - reduction

6 glycerate-3-phosphates are reduced with 2 ATP (provides energy) and 2 reduced NADP (provides electrons through hydrogen atoms) to make 6 triose phosphates and water.

step three - regeneration of RuBP

one of the six triose phosphate molecules can be removed, and some of the molecules can be added together to create hexose phosphate molecules (which make starch), while the rest are used to regenerate RuBP to carry on the cycle.

step four - output

this cycle can result in the creation of glucose-3-phosphate, fatty acids, or glycerol, the latter two being assisted by enzymes.