Glycogen is a carbohydrate
similar to amylopectin
, but larger. It can contain up to 500000 glucose monomer
s. The structure is a complicated branching structure, starting with the basic component of amylose
, a series of 100 to 1000 glucose monomers linked by α(1->4) linkages (similar to maltose
). These molecules are lined up in a branched structure, like the extedending tendrils of a tree. The difference between the branched form of amylopectin and that of glycogen is that glycogen's branches are shorter and more frequent.
As for biological functions, 10% of the liver's mass is made of glycogen, and 2% of muscle mass.