Sensory receptors of the skin GLANDS OF THE SKIN

The integument consists of the skin, and a variety of skin derivatives. In humans, these include hair, nails and several types of glands. In other mammals, these cutaneous appendages include scales, quills, spines, claws, hooves, and horns. The skin consists of a superficial epithelial component, the epidermis, and an underlying layer of connective tissue, the dermis. Together these layers cover virtually the entire external body surface. The skin appendages derive from the epidermis and are therefore morphologically and functionally related to this epithelium. However, as you will see, in the adult some of these structures may have invaginated deeply into the dermis. Keep in mind that the epidermis and its derivatives are avascular; thus they depend on the underlying highly vascularized and innervated dermis for nutritional support.