5E344297-B892-44D4-8C22-D525F07C686D.jpeg

# The Structure of the Skin The skin is composed of three main layers: epidermis, dermis, and hypodermis. ## Epidermis * The outermost layer of the skin. * In most parts of the body it is about 0.1 mm thick. * On the palms of the hands, it can be 1 mm thick or more. * The cells in the epi...

# The Structure of the Skin The skin is composed of three main layers: epidermis, dermis, and hypodermis. ## Epidermis * The outermost layer of the skin. * In most parts of the body it is about 0.1 mm thick. * On the palms of the hands, it can be 1 mm thick or more. * The cells in the epidermis are called keratinocytes and produce a tough protein called keratin. * These keratinocytes die and fall off after some time. * This layer makes the skin waterproof. ## Dermis * Lies under the epidermis and is about four times thicker. * Contains blood vessels that transport blood to the skin. * Also contains nerve cells and touch corpuscles, that transmit information to the brain. * Contains collagen and elastin proteins that give the skin strength and flexibility. * As people age, the number of these proteins reduces, making the skin more fragile. * Hair shafts grow through the dermis and epidermis. * Connected to oil glands, which produce an oily substance. * Contains sweat glands, producing sweat that travels through a tunnel to a small hole in the epidermis (sweat pore). ## Hypodermis * Lies below the dermis. * Contains fat cells. * Overweight people have a thicker hypodermis.