Phosphofructokinase catalyses a reaction early in glycolysis. A scientist studying
respiration in a green aglae notices that over time its activity is decreasing rather than
increasing. What is the best explanation for this observation?
A. ADP is binding to it competitively.
B. The cell is switching to fermentation.
C. NADH is being depleted.
D. ATP is binding to it allosterically.
E. NAD+ levels are too high and therefore pyruvate is accumulating.