Homeostasis Flashcards
(23 cards)
What is homeostasis?
The maintenance of a constant internal environment.
What internal conditions are regulated by homeostasis?
- Temperature
- Blood pressure
- Water concentration
- Glucose concentration
What happens if homeostatic conditions deviate too far from normal?
The body will not function properly and may lead to death without medical intervention.
What is negative feedback?
A process that restores a condition back to normal after a change occurs.
How does negative feedback work when a factor rises?
Control systems are switched on to reduce the factor.
How does negative feedback work when a factor falls?
Control systems are switched on to raise the factor.
What is the main substrate used in respiration for energy?
Glucose.
What are the two hormones that control blood glucose levels?
- Insulin
- Glucagon
When is insulin produced?
When blood glucose rises.
What effect does insulin have on liver and muscle cells?
Stimulates them to convert excess glucose into glycogen for storage.
When is glucagon produced?
When blood glucose falls.
What effect does glucagon have on liver and muscle cells?
Stimulates them to convert stored glycogen into glucose to be released into the blood.
What is Type 1 diabetes?
A condition where blood glucose levels cannot be regulated due to insufficient insulin production.
What are common signs and symptoms of diabetes?
- High blood glucose level
- Presence of glucose in urine
- Extreme thirst
- Weakness or tiredness
- Blurred vision
- Weight loss
- Frequent urination
- Loss of consciousness in extreme cases
How can Type 1 diabetes be treated?
By injecting insulin.
What is the optimal temperature for enzyme activity in the human body?
Around 37°C.
What happens to enzymes if body temperature increases beyond the optimal range?
Enzymes will denature and become less effective.
What part of the brain controls body temperature?
Hypothalamus.
How do temperature receptors in the skin contribute to temperature regulation?
They send nerve impulses to the hypothalamus.
What is vasodilation?
The widening of arterioles in the skin to increase blood flow for heat loss.
What role does sweating play in temperature regulation?
Increases evaporation to remove latent heat from the body.
What happens during vasoconstriction?
Arterioles in the skin narrow, reducing blood flow and heat loss.
What is shivering?
Involuntary contraction of skeletal muscles to release heat energy.
