Hair grow on skin of the person and represent horn formation of the extended cylindrical form. They cover practically all surface of a body, except for soles of legs, palms, bends of extremities, lips.
Hair perform a number of important functions. First of all they act as a protective barrier. Head hair interfere with its overheating, overcooling and traumatizing. In hot season they do not allow the head to heat up. For this reason representatives of negroid race have hair more curly, they promote the best thermal control. In cold time the head hair detain and keep heat.
Eyelashes protect eyes, and hair in nostrils and external ears interfere with hit in an organism of foreign matters and also dirt and dust. Eyebrows protect skin from sweat. Body hair as well as on the head, participate in heat exchange. The air which is between hairs promotes saving of heat and works like clothes. The more hair become straight, the they hold more air. The flat muscle which forms so-called "goose-pimples" is connected to each hair bulb. Excitement of these muscles happens under the influence of cold or emotional fear.
Hair on a pubis and under mice grow not accidentally too. Exactly here congestions of lymph nodes to which overheating is harmful are located. Besides, pubic and axillary hair are capable to increase sexual appeal as they catch the liquid emitted by sebaceous glands. When this secret collapses bacteria from the external environment, the musky smell operating as the sexual activator is formed. There is an opinion that hair under mice and on a pubis reduce the friction arising at the movement of hands and legs. But besides other, hair perform also esthetic function. They serve the purposes of beauty and appeal of the person. People create various hairstyles, hairstyles, give various shades to draw attention of representatives of an opposite sex. Beautiful and shiny hairs are not only attractive from the esthetic point of view, but also signal about the state of health of their owner.