This animation shows an enlargement of a section of skin to highlight an individual sweat gland. The gland then expels sweat onto the surface of skin.
There are more than two and a half million eccrine sweat glands all over the body. They lie deep in the skin and are connected to the surface by coiled tubes called ducts. Sweat (perspiration) is a liquid mixture made up of 99% water and 1% salt and fat. Up to a quart of liquid a day can evaporate through the sweat glands.
As the body becomes overheated, a person sweats, which evaporates and cools the body. When a person becomes frightened or nervous, like being pinned under heavy weights, the body begins to sweat on the palms and forehead, as well as the soles of the feet and in the armpits. These are the sites where sweat glands are most abundant.
Reviewed last on: 9/12/2008
Michael Lehrer, M.D., Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network.