In the carbon fixation step of the Calvin cycle, ribulose- 1,5- bisphosphate a five- carbon compound) is carboxylated to produce
A) glucose.
B) acetyl CoA two carbons) and oxaloacetate four carbons).
C) citric acid.
D) 2 three- carbon compounds.

Question

Quizplus · Accepted Answer

Ribulose-1,5-bisphosphate is carboxylated with carbon dioxide to form two molecules of 3-phosphoglycerate, which are three-carbon compounds. Therefore, the correct answer is D - 2 three-carbon compounds. Glucose, acetyl CoA and citric acid are not products of the carbon fixation step of the Calvin cycle.

In the Carbon Fixation Step of the Calvin Cycle, Ribulose-