AP BIOLOGY

Detailed explanation-1: -Phosphofructokinase (PFK) utilizes ATP to phosphorylate fructose-6-phosphate to fructose-1, 6-bisphosphate . As a regulatory enzyme of glycolysis, PFK is negatively inhibited by ATP and citrate and positively regulated by ADP.

Detailed explanation-2: -An enzyme called hexokinase uses the energy of ATP to add a phosphate group to glucose to form glucose-6-phosphate. Similarly, an enzyme, called phosphofructokinase, uses ATP to add a phosphate group to fructose-6-phosphate to form fructose-1, 6-diphosphate.

Detailed explanation-3: -The enzyme hexokinase phosphorylates or adds a phosphate group to glucose in a cell’s cytoplasm. In the process, a phosphate group from ATP is transferred to glucose producing glucose 6-phosphate or G6P. One molecule of ATP is consumed during this phase.

Detailed explanation-4: -The enzyme phosphofructokinase transforms fructose-6-phosphate to fructose-1, 6-diphosphate. Decreased activity of this enzyme results in increased muscle glycogen stores of normal structure and increased concentration of glucose-6-phosphate and fructose-6-phosphate (Musumeci et al., 2012).

Detailed explanation-5: -Phosphofructokinase composed of PFKM subunits is involved in the sequence of events that breaks down glycogen to provide energy to muscle cells. Specifically, the enzyme converts a molecule called fructose-6-phosphate to a molecule called fructose 1, 6-bisphosphate.