Final answer:
Polysaccharides, like cellulose and starch, are complex carbohydrates that store energy and provide structural support.
Step-by-step explanation:
Polysaccharides, such as cellulose and starch, are complex carbohydrates made up of many monosaccharide units. The main function of polysaccharides is to store energy and provide structural support. Cellulose, found in plant cell walls, is a linear chain of glucose molecules, while starch is a branched polymer of glucose.