Integumentary System Functions

What are the principal functions of the integumentary system?

The integumentary system includes the skin, hair, and nails. The skin—the major organ of the system—has many different functions, but its most important function is protection. The integumentary system serves as a barrier against infection and injury, helps to regulate body temperature, removes wastes from the body, gathers information, and produces vitamin D.

Protection The skin forms a barrier that blocks out pathogens and debris and prevents the body from drying out. The skin also provides protection from the sun's ultraviolet radiation. Nails, which protect the tips of fingers and toes, are also produced by the skin.

Body Temperature Regulation The skin helps to regulate body temperature by releasing excess heat generated by working cells, while keeping in enough heat to maintain normal body temperature. Hair also helps to prevent heat loss from the head.

Excretion Small amounts of sweat are constantly released from your sweat glands. Sweat contains waste products such as urea and salts that need to be excreted from the body.

Information Gathering The skin contains several types of sensory receptors. It serves as the gateway through which sensations such as pressure, heat, cold, and pain are transmitted from the outside environment to the nervous system.

Vitamin D Production One of the skin's most important functions is the production of vitamin D, which is needed for absorption of calcium and phosphorus from the small intestine. Sunlight is needed for one of the chemical reactions that produce vitamin D in skin cells.