Homeostasis

Question 1

What is Homeostasis?

Answer 1

Regulation of internal environment
Maintaining Equilibrium
Self-regulation to maintain a ‘normal’ state
System of feedback control to stabilise health

Question 2

Give an example each for internal and external change conditions.

Answer 2

Internal - blood becoming too acidic or containing too much sugar
External - from traumatic injury or changes in temperature

Question 3

Define the word Homeostasis.

Answer 3

Homeo = same
Stasis = still, inactive
Homeostasis = maintenance of a balanced internal environment

Question 4

Why do variations occur in Homeostatic Ranges?

Answer 4

Physical activity - e.g changes in metabolic need
Due to ageing - e.g increased blood pressure
During illness

Question 5

What is the job of the compensatory mechanism?

Answer 5

It’s job is to restore a Homeostatic imbalance when a fluctuation deviates outside of the optimal range

Question 6

What are the three components of the compensatory mechanism and what do they do?

Answer 6

Detector – sensory receptor – picks up change
Control – interprets change & co-ordinates response
Effector – motor response – reaction to correct change

Question 7

What are the two forms of feedback?

Answer 7

Positive and Negative

Question 8

What is Negative Feedback and give an example of it working.

Answer 8

Negative feedback reverses a change or imbalance to return the body to Homeostasis, one example is when your body becomes too hot, a cooling mechanism is used such as sweating

Question 9

What is Positive Feedback and give an example of it working.

Answer 9

Positive feedback strengthens a change or imbalance and makes the response stronger e.g. uterine contraction during labour to help push the baby out

Question 10

What are 3 ways Homeostasis can be restored when a person becomes ill?

Answer 10

Medically - manage symptoms, drug therapy
Surgically - repair of blood vessels, removal of blockages
Lifestyle changes - losing weight, changing diet