What is the primary role of glycogen phosphorylase in carbohydrate metabolism?

A To synthesize glycogen from glucose
B To break down glycogen into glucose-1-phosphate ✓
C To convert glucose-6-phosphate to glucose-1-phosphate
D To phosphorylate hexokinase

Explanation

Glycogen phosphorylase is a key enzyme in the breakdown of glycogen to glucose-1-phosphate, which is then converted to glucose-6-phosphate and either used for glycolysis or dephosphorylated to glucose for release into the bloodstream.

Mnemonic

Phosphorylase = 'breakdown' enzyme

Source

Lehninger Principles of Biochemistry
Carbohydrate Metabolism Biochemistry Glycogen Metabolism Medium NURSING Confidence: high