1. The Skin

2. Skin Made of three layers – epidermis – Dermis – hypodermis

3. Epidermis Outer, thinnest layer – Outermost cells of skin are dead and rub off when you touch anything – New cells constantly produced at base of epidermis – Cells produce melanin, which is a pigment that protects your skin and gives it color

4. Dermis Middle layer – Thicker than epidermis – Contains blood vessels, nerves, muscles, oil, sweat glands

5. Hypodermis Fatty layer – Insulates the body

6. Functions of Skin 1.Protection  forms a protective covering over body that prevents injury 1.Disease causing pathogens cannot pass through skin 2.Prevents excess water loss 2.Sensory response  nerve cells in the skin detect and relay information to brain 3.Formation of Vitamin D  helps body absorb calcium 4.Regulation of body temp 1.Blood vessels in skin help release or hold heat 2.Perspiration from sweat glands eliminate excess body heat by evaporation 5.Elimination of wastes (through sweat glands)

7. Skin Injuries When injured, skin produces new cells and repairs tears – Bruises happen when tiny blood vessels beneath skin burst and leak into surrounding tissues – When you have a cut, a scab forms to prevent bacteria from entering your body – Skin cells grow beneath the scab and fill in gap of torn skin

8. Severe Injuries Doctors able to repair severe skin damage – Skin grafts  pieces of skin cut from one part of a person’s own body and moved to injured area – Sometimes use cadavers to prevent infections until a victim’s skin heals – Can also grow large sheets of epidermis from small pieces of victim’s healthy skin