1. The Skin? What does it do?

2. What is skin? Skin is the largest organ of the body It gives a tough, flexible covering to the body Divided into 3 main sections Epidermis – the top layer Dermis – middle layer Subcutaneous layer – the bottom layer Skin has 5 main functions

3. Sensation Skin lets us feel: Touch Pressure Pain Heat Cold Recognise objects by feel and shape

4. Heat regulation Temperature control Normal body temperature is 36.8°C Blood supply & sweat glands mainly control body heat loss. Heat can be distributed by blood circulation to the body Sweating also helps control heat by lowering temperature

5. Absorption Skin acts as a waterproof barrier UV rays are absorbed stimulating melanin production Small amounts of creams etc may be absorbed by the very top layer of the skin only.

6. Protection Outer skin surface protects against bacteria by forming the Acid Mantle (sebum & sweat) Prevents absorption by creating a barrier Acts as a cushion for underlying structures Acts as a waterproof coating preventing vital water loss Contains Melanin which absorbs UV rays – Tanning

7. Elimination/Excretion Sweating helps get rid of waste products like water and salt through the surface of the skin 2 types of sweat, 1 happens all the time and you don’t know about it. The other only when you are hot or stressed

8. Nutrition Storage for fat, providing an energy store. Produces Vitamin D – chemical reaction when sunlight is in contact with the skin