Controlling Temperature

Cards (14)

Which part of body detects change in temperature?
Hypothalamus
Describe what happens when it's too hot
Hypothalamus detects it
Erector muscles relax so hair lies flat
Lots of sweat produced
Vasodilation occours
What does sweat contain?
Water and salts
What happens when sweat evaporates?
Transfers energy from skin to environment, cooling you down
Which blood vessels vasodilate?
Blood vessels close to surface of skin
What is vasodilation? 
Blood vessels widen
Why does vasodilation help cool you down?
Allows more blood to flow near to the surface of skin so it can transfer more energy into surroundings therefore cooling you down
Describe what happens when you get too cold?
Hypothalamus detects it
Erector muscles contract, causing hairs on your muscles to stand on end
Very little sweat produced
Vasoconstriction
Shivering
Why does your hair stand on end?
Trap and insulates layer of air, which keeps you warm
What is vasoconstriction?
Blood vessels become narrower
Why does vasoconstriction occour?
Limits blood flow near surface, so less energy transferred to surroundings
What is shivering?
Muscles contract automatically
Why does shivering occour?
It needs respiration which transfers some energy to warm the body
How does the hypothalamus detect a change in a person's body temperature?
Contains receptors that are sensitive to blood temperature in the brain
Receives impulses from receptors in the skin that provide information about external temperature