What is glycogen ? How is it different from starch?

Explanation

Starch is not a single compound but is mixture of two components a water soluble component called amylose (15-20%) and water insoluble component called amylopectin (80– 85%). Amylose is a linear polymer of `alpha`-D-glucose. But both glycogen and amylopectin are branched polymers of `alpha`-D-glucose , however, glycogen is more highly branched than amylopectin. Whereas amylopectin chains consist of 20-25 glucose units, glycogen chains consist of 10-14 glucose units.