Final answer:
The structure difference between α-amylose and cellulose lies in their glycosidic links: α-amylose has α-1,4-glycosidic bonds and forms a helical structure, while cellulose contains β-1,4-glycosidic linkages leading to a rigid, linear fiber structure.
Step-by-step explanation:
The primary differences between α-amylose and cellulose are found in the types of glycosidic bonds and the resulting structures they form. α-Amylose consists of α-D-glucose units linked by α-1,4-glycosidic bonds, leading to a helical structure due to hydrogen bonding, which contains six glucose units per turn. Conversely, cellulose is composed of glucose units connected by β-1,4-glycosidic linkages, creating a more extended and linear structure that allows extensive hydrogen bonding between OH groups on adjacent chains, resulting in tightly packed fibers.
These structural differences account for the varying physical properties of amylose and cellulose. Cellulose, due to its β-linkages, forms a rigid structure that is insoluble in water and resists being broken down by digestive enzymes in the small intestine. On the other hand, α-amylose, with its α-linkages and helical structure, interacts more readily with other substances, such as iodine, forming a colored complex.