Polysaccharides are complex . There are several complex carbohydrates: all are chains of smaller sugar molecules.
Most common complex carbohydrates are starch , stored by plants and glycogen , stored in animals.
Most abundant polysaccharide is cellulose , present in cell wall of plants. In animal kingdom, most abundant polysaccharide is chitin , present in exoskeleton of arthropods.
Complex polysaccharide molecules are also present in cell wall of , as well as in fungus.