Human structures of epidermal origin

A variety of special structures of the skin are derived from the epidermal tissue. In humans these include the hair, nails, and all types of skin glands. These structures begin as irregularities in the interface zone between the stratum basale and the underlying dermis. At the locations where these structures orignate the epidermis forms an inward growth that extends these epidermal tissues deeper into the dermis. Once established, these root-like epidermal extensions mature into the intended structure, hair, nail, sebaceous gland, sweat gland, etc.