3a.4 - Homoeostasis Flashcards
1
Q
What is homoeostasis?
A
The maintenance of a constant internal environment
2
Q
What six things need to be controlled inside the body?
A
- Temperature
- Water
- Ion content
- Blood sugar levels
- Carbon dioxide
- Urea
3
Q
What temperature do enzymes in the body work best at?
A
37C
4
Q
Which part of the brain controls temperature?
A
Hypothalamus
5
Q
How does the hypothalamus control temperature? (3)
A
- Contains receptors that are sensitive to the temperature of the blood flowing through the brain
- Also receives data from skin
- Makes the body respond to try and cool you down or warm you up
6
Q
What happens when you’re too hot? (3)
A
- Hairs lie flat
- Sweat is produced
- Blood vessels dilate so more blood flows to the skin
7
Q
What happens when you’re too cold?
A
- Hairs stand up
- No sweat
- Skin capillaries constrict to close off the skins blood supply
8
Q
What are the roles of the kidney? (3)
A
- Removal of urea from the blood
- Adjustment of ions in the blood
- Adjustment of water content in the blood
9
Q
What is urea?
A
A waste product from amino acids turning into fats and carbohydrates
10
Q
How is water lost from the body? (3)
A
- Urine
- Sweat
- Breath
