1. Homeostasis
controlling conditions in the body

2. Homeostasis – controlling conditions in
the body
Several things need to be controlled:
• Water
• Ions and minerals
• Blood sugar
• Temperature

3. Water
Breathing
In: Out:
Water Sweating
Food (eg vegetables) Urine (from the kidneys)
Sweating
Key organ is the kidney Urine (from the kidneys)

4. Ions
Ions (eg calcium, sodium, potassium)
Sweating
Food
Urine from the kidneys

5. Blood sugar
In: Out:
Drink and Exercise
Food Insulin – a hormone

6. Temperature – needs to be 37°C
Exercise
Sweating
Warm
Blood circulation
weather
Hairs on body
Enzymes work best at 37°C
If too high enzymes can’t work.
Too low the enzymes can’t work

7. Keeping a constant temperature
To keep warm: To keep cool:
- Shivering – uses -Sweating
energy
-Vaso-dilation
- Releasing energy
from food
- Vasoconstriction
- Exercising
Controlled by the hypothalamus