Controlling body temperature

Flashcards by karen.cruicks, updated more than 1 year ago
Created by karen.cruicks over 7 years ago


B3 Flashcards on Controlling body temperature, created by karen.cruicks on 04/10/2013.

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Hypothermia If your core body temperature falls below 35 degrees Celsius you are suffering from hypothermia and the normal working of your body is affected. Old people, very young children and people exposed to bad weather conditions are at risk.
The signs of Hypothermia The first signs of Hypothermia are extreme tiredness and not wanting to move. You may not even realize how cold you are. Your skin feels cold to the touch and your face goes greyish- blue and puffy, with blue lips. You become drowsy and your speech becomes slurred. Eventually you actually stop shivering as your enzymes stop working. If your body temperature becomes too low you will become unconscious and may die.
How common is Hypothermia? About 30,000 people die of Hypothermia every year in the UK alone, mainly during the winter months. This contributes to what is known as the excess winter mortality (EWM).
What happens when you get too hot? Excess heat is also bad for people. Heat stroke happens when your body gets too hot. The most common cause is very hot, humid weather, often combined with exercise. Exercise releases energy. When it is very hot and humid, your sweat cannot evaporate to cool you down. If you don't drink enough in very hot weather you can't make sweat so you can't lose energy so your body temperature keeps going up. You stop sweating and your skin is red and flushed. You can become confused, see things that aren't there (hallucinations) and eventually go into a coma and die. The very old and the very young are at risk - so are fit, active young people.
Are there certain parts of the body that can get hotter or colder than 37 degrees Celsius? The skin and some other parts of the body can get hotter or colder than 37 degrees Celsius
How does the body control temperature? Part of your brain acts like a thermostat. We call it the thermoregulatory centre. It checks the temperature of the blood passing through your brain. It receives impulses from temperature receptors in your skin.
What does the thermoregulatory centre do if the body temperature is too high or too low? If your core temperature is too high or too low, your thermoregulatory centre sends impulses to your skin and muscles. These affect muscles, sweat glands and the blood vessels to your skin. Evaporation of sweat cools your body. Shivering muscles are contracting muscles. To contract, they use energy from respiration. Some of this energy is released as heat.
What happens when your core temperature is too high/ too low? Too High No shivering, sweating, blood vessels supplying your skin capillaries dilate (widen) so more blood can flow through Too Low Shivering, no sweating, blood vessels supplying you skin capillaries constrict so less blood can flow through meaning less heat is lost to the surroundings.
Thermoregulatory centre
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