What are the basic units of polysaccharides?

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Polymers are made up of monomers. Polysaccharides are also polymers (and that is why their name contains 'poly') and are made up of monosaccharides. These monomers are simple sugar molecules and contain multiple hydroxyl groups (`OH^-`). Some examples of monosaccharides are glucose, fructose, etc. The monosaccharides contain a number of carbon atoms. Polysaccharides are formed when monosaccharides are linked through glycosidic bonds. For example, starch, a polysaccharide, is made up of glucose (a monosaccharide). Similarly, glycogen is also made up of glucose molecules connected through glycosidic bonds. Cellulose, which forms plant cell walls is also a polysaccharide, made up of the monosaccharide glucose.

Some polysaccharides are also composed of disaccharides, which are formed by covalent linkage of two monosaccharides. Sucrose and lactose are disaccharides. An example of a polysaccharide composed of disaccharides is hyaluronic acid.

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