What are the subunits and functions of carbohydrates?
Monosaccharides, disaccharides and polyssaccharides; their function is mainly energy storage and structural.
Monossacharides are the basic units that make up the carbohydrates. They are usually broken down by our metabolism in order to produce chemical energy (ATP) and thus keep our cells working. An example of monossacharide is the glucose .
Disaccharides are the most common form of "sugar" found in nature, rather than monossacharides. They are the carbohydrates that we actually eat, and are made of two monossacharides bonded together; in order to produce energy, we must first break dissacharides down into monossacharides. Some examples are lactose, found in milk, and saccharose, found in beets.
Polyssaccharides are long chains of monossacharides. They are much more stable than mono or dissacharides, and thus can be used for different functions: the first one is structural, such as cellulose, found in the leaves and stems of plants, and chitin, found in the carapaces of insects. The second function is long-term energy storage, such as glycogen in animals and starch in plants; these can be broken down by the organism into monossacharides in order to produce energy.