Question

In muscle tissue, the rate of conversion of glycogen to glucose 6-phosphate is determined by the ratio of phosphorylase a (active) to phosphorylase b (less active). Determine what happens to the rate of glycogen breakdown if a muscle preparation containing glycogen phosphorylase is treated with (a) phosphorylase kinase and ATP; (b) PP1; (c) epinephrine.

Answer 1

Answer:

(a) When the enzyme phosphorylase is allowed to treat with the ATP and phosphorylase kinase, this helps in the activation of the more active form of the phosphorylase. This increase the process of the glycogen breakdown in the cell.

(b) PP1 ( protein phosphatase 1) removes the phosphate group from the substrate that results in the activation of the less active form of the enzyme. The process of glycogen breakdown in the cell will decrease.

(c) The hormone epinephrine causes the release of cAMP that increases the kinase activity. The active form of the enzyme predominates and increases the glycogen breakdown in the body.