1. Capillaries near the surface of the skin open when your body needs to cool off and close when you need to conserve heat 2. Thinnest layer of the skin 3. Nervous systern depends on neurons embedded in your skin to sense the outside world 4. Blackheads and acne are common to person with oily skin. 5. The hypothalamus also causes dilation of the blood vessels of the skin, allowing more blood to flow into those areas, causing heat to be released from the skin surface. 6. Sunscreen protects people from sun's ray. 7. When a microbe gets into the skin (or when the skin is cut) an immune system reaction occurs. 8. A person having black skin lacks melanin 9. When the muscles contract the hair, fur stands. 10. Makes vitamin D through exposure to UV radiation.​