Question

What does Calvin Cycle ultimately result in the formation of when concentrations of CO₂ are low?

1) Glucose
2) Pyruvate
3) ATP
4) NADPH

Answer 1

The Calvin Cycle results in the formation of glucose when concentrations of CO₂ are low, using ATP and NADPH from light reactions to convert 3-PGA into G3P and ultimately glucose.

Step-by-step explanation:

When concentrations of CO₂ are low, the Calvin Cycle ultimately results in the formation of glucose. The cycle uses chemical energy in the form of ATP and NADPH from the light reactions to power the synthesis of glucose through a series of reactions. Starting with carbon fixation, where CO₂ is incorporated into organic molecules, and followed by the reduction phase, this energy is used to convert 3-phosphoglycerate (3-PGA) into glyceraldehyde-3-phosphate (GA3P). GA3P is a key molecule that can be used to form various carbohydrates including glucose, which stores energy captured during photosynthesis. Additionally, the cycle regenerates ribulose-1,5-bisphosphate (RuBP), allowing the cycle to continue.