Phosphofructokinase is an important control enzyme in the regulation of cellular respiration. Which of the following statements describes a function of phosphofructokinase?
A. It is activated by AMP
B. It is activated by ATP
C. It is inhibited by citrate, an intermediate of the citric acid cycle
D. It catalyzes the conversion of fructose-6-phosphate, an early step of glycolysis
E. It is an allosterically enzyme
Answer: E