4.4-regulation of body temperature

• Thermoregulation is the maintenance of core body temperature
• The hypothalamus controls thermoregulation
• Receptors detect changes in internal and external temperatures and are in the skin, liver, skeletal muscles and hypothalamus
• Body heat is lost in convection, conduction, evaporation and radiation
• Convection - air currents moving over the surface of the body
• Conduction - transfer of energy from hotter to cooler objects by direct contact between them
• Evaporation - water on the skin's surface evaporates into the atmosphere taking with it some heat energy
• Radiation is a quality all heated objects have
• Hypothermia is the process of reaching low body temperature and could result in death
• whats happens in certain temperatures

  • mild 32-35 - shivering and increase heart rate
  • moderate 28-32 - shivering sops, decreased heart rate and irrational thinking
  • severe less than 28 - slow palse and coma
• acute hypothermia when someone is exposed to extreme cold
• Exhaustion hypothermia is when someone is exposed o cold and doesn't have metabolic resources to maintain temperature.
• Vasoconstriction is narrowing diameter of blood vessels
• piloerection is a response when a mammal is fearful, aggressive in shock or cold
• Shivering is a reflex action that increases the rate of heat loss from the body
• behaviours to conserve heat

  • exercise
  • hot bath
  • reduced exposed body
  • hot drink
• hyperthermia is where the body temp reaches above average
• hypothermia can be recognised by the following

  • extertional - extended droids of time in hot conditions
  • situational - can happen in hot irl situations
• hypothalamus signals ’cool down’ insertions and effectors respond and increase blood flow
• vasodilation is the first response when the body has irregular temperatures
• process of vasodilation

  1. sphincter relaxes allowing blood flow
  2. vasodilation
  3. increasing blood
  4. increase in heat loss to make person less hot
• sweating is a cooling mechanism that removes heat from the body by evaporation of sweat
• behaviours for heat loss

  • remove clothes
  • cold showers
  • rest in shade
  • ice pack
  • being right at a fan