Both starch and cellulose contain a large number of α -D(+)-glucose units.
Starch consists of two components:
1. Amylose which is a linear polymer and
2. Amylopectin which is a branched polymer but in both the D-glucose units are linked through α -glycosidic linkage between C1 of one glucose with C4 of next glucose unit. In amylopectin branching occurs by C1- C6 glycosidic linkage.
Cellulose is only a linear polymer of Dglucose units joined through β -glycosidic linkage between C1 of one glucose with C4 of next glucose unit.
