Thermoregulation

• Homeostasis


  Maintaining a constant internal environment
• Regulation


  Controlling at a particular level
• If you are too cold, you will experience contraction
• Vasoconstriction allows less thermal energy to be transferred to the skin
• Body hairs will stand on end, trapping a layer of insulating air close to the skin, reducing heat loss
• If you are too hot, you will experience vasodilation
• Vasodilation allows more thermal energy to be transferred to the surroundings
• Body hairs will lie flat, reducing insulation and increasing heat loss
• Shivering warms you up because it requires muscle contraction which releases energy
• Sweating cools you down because water evaporation uses thermal energy
• Skin structures


  • Sweat pore
  • Sweat gland
  • Hair follicle
  • Vein
  • Capillary
• The sweat gland produces a salty colourless liquid which passes through the sweat pore onto the surface of the skin when we get too hot
• The hair grows from a hair follicle in the dermis layer of the skin
• The arrector pili muscle is connected to the hair follicle and when it contracts, it pulls the hair upright to trap air and provide insulation
• Arteries carry oxygenated blood from the heart and lungs, while veins carry oxygen-depleted blood back to the heart and lungs
• Capillaries are smaller, thinner blood vessels that feed the cells of the skin