Adrenaline stimulates glycogen breakdown in skeletal muscle cells by ultimately activating glycogen phosphorylase, the enzyme that breaks down glycogen. Which of the following statements below is false?
a. A constitutively active mutant form of PKA in skeletal muscle cells would lead to a decrease in the amount of unphosphorylated phosphorylase kinase.
b. A constitutively active mutant form of PKA in skeletal muscle cells would not increase the affinity of adrenaline for the adrenergic receptor.
c. A constitutively active mutant form of PKA in skeletal muscle cells would lead to an excess in the amount of glycogen available.
d. A constitutively active mutant form of PKA in skeletal muscle cells would increase the amount of phosphorylated glycogen phosphorylase.
e. A constitutively active mutant form of PKA in skeletal muscle cells would lead to an excess in the amount of glucose available.

This occurs in the process of Glycogenolysis. The process involves breaking down of glycogen to glucose -1- phosphate and glycogen which helps in the release of glucose into the blood stream to prevent hypoglycemia(low blood sugar). The glucose-1-phosphate is later converted to glucose -6-phosphate. The latter enters the glycolytic pathway in which the reaction is catalysed by the enzyme phosphoglucomutase.

This homeostatic glucose regulation is regulated by the protein kinase(PKA)/ cAMP pathway in the skeletal muscles, the liver and the pancreas.

eyitbay eyitbay · Answer 2 · 2020-05-12T02:52:53+02:00

Answer:

c. A constitutively active mutant form of PKA in skeletal muscle cells would lead to an excess in the amount of glycogen available.

Explanation:

This represented the process of Glycogenlysis. The breaking down of glycogen to glucose -1- phosphate and glycogen to release glucose into the blood stream to prevent hypoglycemia. The glucose-1-phosphate is later converted to glucose -6-phosphate. The latter enters the glycolytic parthway. The reaction is catalysed by the enzyme phosphoglucomutase.

This homeostatic glucose regulation is regulated by the protein kinase(PKA)/ cAMP pathway in the skeletal muscles, the liver and the pancreas. The PKA/cAMP signaling pathway, also regulate glucose uptake, breakdown of glycogen, insulin and glucagon synthesis.