Question

In the carbon fixation reactions, how many molecules of co2 enter the cycle before 2 molecules of g3p are made?.

Answer 1

Six molecules of carbon dioxide are required to complete the Calvin cycle six times, which produces two molecules of G3P.

Step-by-step explanation:

In the carbon fixation reactions of the Calvin cycle, three molecules of carbon dioxide (CO2) must enter the cycle to produce one molecule of G3P (glyceraldehyde-3-phosphate). Therefore, to make two molecules of G3P, requires six turns of the cycle, with six molecules of CO2 being fixed. In this process, each CO2 molecule is attached to a five-carbon sugar named RuBP (ribulose bisphosphate), catalyzed by the enzyme RuBisCO. Each CO2 combines with RuBP to form two molecules of 3-phosphoglycerate (3-PGA), which are then reduced to two molecules of G3P using electrons supplied by NADPH. In summary, for each three turns of the cycle, one G3P molecule is produced and exported while the rest of the G3P molecules are used to regenerate RuBP, enabling the cycle to continue.

Answer 2

three molecules of CO2 Must enter the cycle.