Control Of Body Systems (Homeostasis) Flashcards
What is homeostasis?
The maintenance of a stable internal environment
What things are controlled through homeostasis?
Temperature, blood pH, blood glucose
What happens to the temperature when the rate of metabolic reaction increases?
It also increases
What happens if the body temperature gets too high (e.g. 40°C)?
Enzymes denature and reactions stop
Why do enzymes denature in high temperatures?
They denature as some of the hydrogen bonds break
What happens to the active site of denatured enzymes?
It changes and the enzyme and substrate no longer fit together
What happens to enzymes if body temp gets too low how does this affect of the rate of metabolic reactions?
Enzyme activity is reduced which slows the rate of metabolic reactions
What happens if blood pH is too high/low?
Enzymes denature as ionic+ hydrogen bonds break so the active site changes
What is the optimum blood pH?
pH 7
What happens if blood glucose conc is too high?
Water potential in blood is reduced so water molecules diffuse out of cells + into blood via osmosis
What happens if blood glucose conc is too low?
Cells aren’t able to carry out normal activities as there isn’t enough glucose for respiration to provide energy
How does negative feedback work?
Receptors detect when a level’s not normal. Effectors work to counteract the change (bring the level back to normal)
When may negative feedback not work?
If the change is too big
What is a benefit of having multiple negative feedback systems?
A faster + more controlled response to changes
How does positive feedback work?
Effectors further increase the level (of the thing that changed) away from the normal level.
