AP BIOLOGY

Detailed explanation-1: -In the Calvin cycle, carbon atoms from CO2start text, C, O, end text, start subscript, 2, end subscript are fixed (incorporated into organic molecules) and used to build three-carbon sugars. This process is fueled by, and dependent on, ATP and NADPH from the light reactions.

Detailed explanation-2: -The reactants are CO2, NADPH, and ATP.

Detailed explanation-3: -Answer and Explanation: In order to produce sugar (usually in the form of glucose or fructose), the Calvin cycle uses atmospheric carbon dioxide, ATP and NADPH (both produced in the light reactions) as reactants to create glyceraldehyde-3-phosphate (a 3-carbon sugar).

Detailed explanation-4: -In the Calvin cycle, carbon dioxide (CO2) molecules are fixed to sugar with the help of an enzyme called RuBisCO. RuBisCO is short for ribulose-1, 5-biphosphate carboxylase/oxygenase. It is the most abundant protein on Earth.

Detailed explanation-5: -The key step in the Calvin cycle is the event that reduces CO2. CO2 binds to RuBP in the key process called carbon fixation, forming two-three carbon molecules of phosphoglycerate.