Mammalian skin anatomy. Cutaway illustration of the anatomy of mammalian skin, showing some of the main structures. These include hair follicles, sweat glands (yellow), and arterial (red) and venous (blue) blood vessels. Nerves (light green) are also shown, together with Pacinian corpuscles (dark green), which sense vibration and pressure. The skin layers are also shown: the epidermis (top), the dermis (middle), and the hypodermis (bottom).