Photorespiration reduces the net carbon fixed by the Calvin cycle by _______ percent.
A) 0.02
B) 0.21
C) 2.1
D) 25
E) 70

Question

Quizplus · Accepted Answer

Photorespiration reduces the net carbon fixed by the Calvin cycle by 25 percent. During photorespiration, RuBP reacts with oxygen instead of carbon dioxide, creating a product that cannot be used in the Calvin cycle. This means that fewer molecules of carbon dioxide are fixed into organic compounds, reducing the overall efficiency of photosynthesis by 25%.

Photorespiration Reduces the Net Carbon Fixed by the Calvin Cycle