There are 8 blood types, made from four different blood ... The skin, made up of three layers: the Epidermis, the Dermis and the Hypodermis, is an external organ. It serves as a very important ...

The skin contains three layers: The epidermis, dermis and a layer of fatty tissue. Structures within these layers are involved in thermoregulation. Sweat glands in the dermis release more sweat ...