Medical Chemistry Practice Test 2026 – Complete Exam Prep

The main idea is that these two glucose polymers differ in origin and role: cellulose is the structural polysaccharide formed by plants, while glycogen is the storage polysaccharide formed by animals. This distinction matters because it reflects how the molecules are built and used. Cellulose has beta-1,4 glycosidic bonds, which run in straight, unbranched chains that pack tightly into rigid fibers for plant cell walls. Glycogen, in contrast, has alpha-1,4 linkages with numerous alpha-1,6 branches, creating a highly branched, compact molecule ideal for rapid glucose release during energy needs in animals. So the statement that cellulose comes from plants and glycogen comes from animals best captures the fundamental difference in their biological roles and structures.