Vasodilation & Vasoconstruction

Cards with brief descriptions of Vasodilation and Vasoconstriction.

Vasodilation & Vasoconstriction

  • Blood temp. monitored the hypothalamus in the brain.
  • Hot conditions - blood vessels dilate, allowing more blood flow to the skin capillaries.
  • Vasodilation - heat is lost from surface of skin by radiation.
  • Cold conditions - blood vessels constrict, reducing blood that flows through skin capillaries.
  • Vasoconstriction - Less heat lost from surface of skin by radiation.
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  • Occurs when body is exposed to low temperatures for long periods of time.
  • Body can't replace heat as fast as it's being lost.
  • If untreated, can lead to death.
  • Common cause, when core body temperature falls below 35 degrees celcius.
  • Symptoms - grey skin colour, amnesia, shivering, slurred speech, confusion, loss of co-ordination, cold skin.
  • Treatments - raising core body temperature, insulating body, drinking warm drinks.
  • Should not rub/massage the skin because it brings blood to the surface, causes more heat to be lost.
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Heat Stroke

  • Heat Stroke - uncontrolled increase in body temperature.
  • Increased sweating due to very hot temperatures leads to dehydration.
  • Dehydration - stops sweating from occuring, leads to core body temperature increasing further.
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