2. The skin is composed of 2 layers: 1. Epidermis – the outermost layers of cells 2. Dermis – below, a thicker layer of tissue containing fat, blood vessels, hair follicles and nerves

3. Epidermis Outer layers only dead cells and no blood vessels Keratin hardens the cells, making the surface waterproof Bottom layers produce new cells and melanin which colours the skin

4. Dermis Living cells Contains blood vessels that help regulate body temperature All tissues are held together by fibres

5. Ridges Where the dermis and epidermis meet, there is a wave like layer that forms many ridges These patterns show through the surface of the skin = fingerprints

6. Nails Hard structures produced by epidermis These cells lose their cytoplasm which is replaced by keratin making them hard and durable

7. Hair Hair is a sensory organs with nerve endings in the root The hair acts as tiny trigger to let the body know something is touching it Men and women have the some amount of hairs but women have finer hair