Body temperature control

• What is the optimum temperature for enzymes in the body?


  37°C
• Where is the thermoregulatory centre located?


  In the brain
• What type of receptors does the thermoregulatory centre contain?


  Receptors sensitive to the temperature of the blood
• What additional information does the thermoregulatory centre receive?


  Impulses from temperature receptors in the skin
• What happens when the core body temperature is too high?


  1. Temperature receptors detect high core body temperature.
  2. The thermoregulatory centre receives this information.
  3. Effectors, like sweat glands, produce a response to cool the body down.
• What happens when the core body temperature is too low?


  1. Temperature receptors detect low core body temperature.
  2. The thermoregulatory centre receives this information.
  3. Effectors, like muscles, produce a response to warm the body up.
• How do effectors work to maintain body temperature?


  Some effectors work antagonistically to achieve a precise temperature
• What are the responses when the body is too hot?

  • Sweat is produced and evaporates from the skin.
  • Blood vessels supplying the skin dilate (vasodilation).
  • More blood flows close to the skin surface.
• What are the responses when the body is too cold?

  • Hairs stand up to trap insulating air.
  • No sweat is produced.
  • Blood vessels supplying skin capillaries constrict (vasoconstriction).
  • Shivering occurs to generate heat.
• What is the purpose of sweating when the body is too hot?


  To transfer energy to the environment
• What is vasodilation?


  Dilation of blood vessels supplying the skin
• What happens to blood vessels when the body is too cold?

  They constrict (vasoconstriction)
• What is the role of shivering when the body is cold?


  To contract muscles and generate heat
• What can happen to people exposed to extreme cold for a long time?

  They can get frostbite
• Why does frostbite occur?


  Blood supply to fingers and toes is cut off to reduce energy loss
• What happens to cells during frostbite?


  They can die and turn black
• What is the core body temperature?


  The temperature inside your body where internal organs are located