During sustained exercise, the ATP/AMP ratio in muscle cells decreases. What effect does this decreased ATP/AMP ratio have on the activity of phosphofructokinase and pyruvate kinase?

Phosphofructokinase and pyruvate kinase are two important enzymes n the glycolytic pathway They are regulated by the levels of ATP and AMP.

Explanation:

Phosphofructokinase and pyruuvate kinase are the most important control element in the glycolytic pathway.High levels of ATP allosterically inhibit the enzyme , thus lowering its affinity for their substrates. ATP elicits this effect by binding to a specific regulatory site that is distinct from the catalytic site. AMP reverses the inhibitory action of ATP, and so the activity of the enzyme increases when the ATP/AMP ratio is lowered. In other words, glycolysis is stimulated as the energy charge falls. Moreover, the use of AMP as an allosteric regulator provides an especially sensitive control

sex cells are usually half's then they find another half and make a fertilize egg