Glycogenolysis

Question 1

What is the purpose of glycogenolysis?

Answer 1

The purpose of glycogenolysis is to breakdown glycogen to glucose in order to release energy

It occurs in the liver, muscle, and kidneys

It occurs in the cytosol of the cell

This is a catabolic reaction

Question 2

What is the 1st reaction of glycogenolysis?

Answer 2

Glycogen to Glucose-1-phosphate + glycogen

Purpose: Remove glucose monomer from glycogen with the input of energy from ATP

Enzyme: Lyase (Glycogen phosphorylase)

Biochemical process: Phosphorylysis

This reaction is spontaneous and irreversible

Question 3

What is the 2nd reaction of glycogenolysis?

Answer 3

Glucose-1-Phosphate to Glucose-6-Phosphate

Purpose: reshuffle the phosphate group

Enzyme: Isomerase (Phosphoglucomutase)

Biochemical process: Isomerisation

Reaction is spontaneous and reversible

Question 4

What is the 3rd reaction of glycogenolysis?

Answer 4

Glucose-6-phosphate to Glucose + Pi

Purpose: Convert glucose-6-phosphate to glucose for energy using H₂O

Enzyme: Hydrolase (Glucose-6-phosphatase)

Biochemical process: Dephosphorylation and hydrolysis

This step only occurs in liver and kidney, NOT muscle

This reaction is spontaneous and reversible