Sweat gland ducts surface through these ridges to give a nonskid surface to the hands and feet that enable us to pick up small objects and perform delicate manipulations. Deeper in the dermis are the roots of skin glands, hair, blood and lymph vessels, nerves, and larger, tougher fibers. The sweat glands are the most common of the skin glands, and they are found all over the body. Approximately two million sweat glands are distributed over the surface of the body. The most numerous are found on the forehead, face, palms of the hands, soles of the feet, groin, and the axilla.
Sweat glands are small, tight coils of cells in contact with a network of capillaries.
Ducts of the gland corkscrew thorough the epidermis to the skin surface. These glands give off a small amount of waste material, but their most important function is to regulate body heat. As the sweat evaporates, it cools the surface of the body. The second group of skin glands are the sebaceous glands which are as numerous in the body as the sweat glands, and produce oils and fats. These glands open into hair follicles and give off an oily substance called sebum.