High School

What happens during the reduction stage of the Calvin Cycle (light-independent reactions)?

a) Conversion of 3-phosphoglycerate into ribulose-1,5-bisphosphate
b) Incorporation of carbon dioxide into RuBP
c) Formation of G3P molecules
d) Regeneration of RuBP from G3P

Answer :

Final answer:

The reduction stage of the Calvin Cycle involves using ATP and NADPH to convert 3-phosphoglycerate into glyceraldehyde 3-phosphate (G3P), a key step in carbohydrate production. The correct answer is c) Formation of G3P molecules.

Explanation:

During the reduction stage of the Calvin Cycle (light-independent reactions), ATP and NADPH are utilized to convert the six molecules of 3-phosphoglycerate (3-PGA) into six molecules of glyceraldehyde 3-phosphate (G3P). This step is essential for the production of carbohydrates.

The reduction reaction involves the gain of electrons by 3-PGA, utilizing energy from ATP and NADPH, which are products of the light-dependent reactions in photosynthesis.

Once the G3P molecules are generated, one G3P molecule leaves the cycle while the others are used to regenerate ribulose-1,5-bisphosphate (RuBP) to continue the Calvin Cycle.