B7 - Controlling Body Temperature and Blood Sugar Flashcards
What is the body’s optimum temperature for its reactions?
37 degrees celcius
What detects external temperature?
Temperature receptors in the skin
What detects the temperature of the blood?
Receptors in the hypothalamus (part of the brain)
What controls body temperature and what process does it use?
The nervous system
Negative feedback
What happens if core body temperature is too high or low?
The hypothalamus receives the information from the temperature receptors,
This triggers the effectors (e.g sweat glands if too hot, or muscles if too cold) to produce a response.
What 2 measures are carried out when the body is too hot?
- Vasodilation
2. Sweat glands produce more sweat
What is vasodilation?
Where blood vessels close to the skin’s surface get wider allowing more blood to get to the surface of the skin. The warm blood loses more of its heat to the surroundings.
How does more sweat reduce body temperature?
When the water in sweat evaporates heat is used which cools the body.
What happens to core body temperature when you are dehydrated and why?
It increases because less sweat is produced
What 2 measures are carried out when the body is too cold?
- Vasoconstriction
2. You shiver
What is vasoconstriction?
Where blood vessels close the the skin’s surface get narrower meaning that less blood gets to the surface of the skin, which retains more heat.
How does shivering increase body temperature?
It increases the rate of respiration and warms the tissue surrounding the muscles.
Which hormone controls the level of sugar in the blood?
Insulin
Why do processed foods cause blood sugar levels to rise?
Because the simple sugars in them are digested and absorbed into the blood very quickly
What happens when blood sugar levels get too high?
The pancreas releases insulin causing sugar to be removed from the blood
