Question

Different types of glycosidic linkage cause glucose polymers to form a helix (e.g., in glycogen) versus a straight chain (e.g., in cellulose). Which statement best explains why?

Answer 1

Cellulose forms a straight chain due to its β-1,4-glycosidic linkages, while glycogen forms a branched structure due to its α-1,4-glycosidic and α-1,6-glycosidic linkages.

Step-by-step explanation:

Cellulose and glycogen are both polymers of glucose, but they have different types of glycosidic linkages. Cellulose has β-1,4-glycosidic linkages, which cause the glucose units to form a straight chain. This straight chain structure allows for a great deal of hydrogen bonding between the adjacent chains, resulting in closely packed fibers. On the other hand, glycogen has α-1,4-glycosidic linkages and α-1,6-glycosidic linkages, which give it a branched structure. The branching prevents the formation of a helix and instead allows glycogen to form highly compact globular structures.