The functions of polysaccharides depend primarily on their form: polysaccharides that take the shape of homopolysaccharides create glucose, which is used to treat shock, while polysaccharides in the form of pectin are added as gels to enhance the texture or flavor of commercial items, such as food products and beverages. Polysaccharides, also called glycan, are the most common naturally occurring types of carbohydrates. Polysaccharides come in several different forms, including homoglycans and heteropolysaccharides or heteroglycans.
Both homoglycans and heteroglycans can be produced naturally or synthetically. In their natural form, homoglycans exist in many types of plants, and are found primarily in plant stems. Heteroglycans, in contrast, are found more frequently in mammals. In animals, heteroglycans serve several important purposes, including giving shape to connective tissues in joints and mammal umbilical cords, forming fluids between joints and contributing to the formation of a substance called heparin, which acts as an anticoagulant. Heteroglycans vary in complexity, which influences their uses. Some types of plant gums contain heteroglycans as does glucuronic acid and sugar. Heteroglycans can be extracted from their sources and used for various purposes, such as repairing damaged tree bark. Polysaccharides are found in many types of plants and animals, including pine trees and conifers, orchid tubers, bacteria, fungi and crustaceans, such as crabs and lobsters.