Answer :
Final answer:
During the regeneration phase of the Calvin Cycle, five G3P molecules are utilized to regenerate RuBP with the help of three additional ATP molecules, allowing the cycle to continue.
Explanation:
During the regeneration stage of the Calvin Cycle (light-independent reactions), the five remaining glyceraldehyde-3-phosphate (G3P) molecules from the cycle are used to regenerate ribulose bisphosphate (RuBP), enabling the system to prepare for more CO₂ to be fixed. It takes three revolutions of the Calvin Cycle to produce enough net carbon to release one G3P into the cytoplasm of the plant cell. Each cycle turn produces two G3Ps, so three 'turns' yield six G3Ps; one is exported, and the remaining five are used in the regeneration of RuBP. This process is fueled by three additional molecules of ATP.