Summarize the general characteristics of carbohydrates and their roles in living organisms.

Carbohydrates are known as major organic molecules. They are composed of hydrogen, carbon, and oxygen. Carbohydrates are basically four types:

1) Monosaccharide: They are known as the simplest carbohydrates such as fructose, and glucose.

2) Disaccharides: They are formed from two, monosaccharides such as lactose, and sucrose.

3) Oligosaccharides: They are formed from 3 to 6 numbers of monosaccharides.

4) Polysaccharide: They are long carbohydrate molecules also known as complex carbohydrates such as cellulose, and chitin.

They are the main source of energy for most of the living things. Structural carbohydrates provides structural support, and protection to the body.