<span>An increase in the amount of ATP in a cell would be expected to inhibit the enzyme and thus slow the rates of glycolysis and the citric acid cycle.</span>
Phosphofructokinase is an allosteric enzyme that catalyzes the conversion of fructose 6-phosphate to fructose 1,6-bisphosphate. This a an early reaction in the glycolysis pathway that is a regulatory step in the pathway. An increase int he amount of ATP in the cell might cause decrease in the amount of phosphofructokinase enzyme by a process called feedback inhibition. Glycolysis process is regulated at various steps in which conversion of fructose 6-phosphate to fructose 1,6-bisphosphate is one of the regulatory step.
Answer: In the presence of oxygen, an increase in the amount of ATP in a cell would be expected to INHIBIT THE PHOSPHOFRUCTOKINASE ENZYME AND SLOWS THE RATE OF GLYCOLYSIS.
I think the correct answer from the choices listed above is option A. Directional selection can be distinguished from disruptive selection by the elimination of extreme variations of traits. Directional selection is a natural selection where an extreme phenotype is favored than others.
