Specific linkages can lead to very specific chemical and biological behavior.
The most important polysaccharides are all composed primarily of glucose units. Starch, on the other hand, is linked by a -linkages. The amylose portion is also a linear polymer, though it can branch somewhat more than cellulose. Amylopectin, another portion of strarch, is much more branched and is water-soluble. Starch is more readily hydrolyzed than cellulose and is thus a storage reservoir for glucose generated from photosynthesis.