Hair and Nails
Hair is produced by cells at the base of structures called hair follicles. Hair follicles are tubelike pockets of epidermal cells that extend into the dermis. Individual hairs are actually large columns of cells that have filled with keratin and then died. Rapid cell growth at the base of the hair follicle causes the hair to grow longer. Hair follicles are in close contact with sebacrous glands. The oily secretions of these glands help maintain the condition of each individual hair.