Homeostasis

Question 1

What is homeostasis?

Answer 1

The physiological arrangements that serve to restore the normal state once it has been disturbed

Question 2

Why is homeostasis important?

Answer 2

Cells function under optimal environments and these conditions need to be consistently met

Question 3

What conditions are important for optimal cell function?

Answer 3

• pH
• Blood sugar level
• Water content/fluid balance
• Body temperature

Question 4

What two general mechanisms can be used to achieve homeostasis?

Answer 4

• Feedback control

- Feedforward control

Question 5

What is negative feedback control?

Answer 5

A decrease/increase in a variable which results in mechanisms to counteract the change in variable

Question 6

What is positive feedback control?

Answer 6

A SMALL change in a variable results in the change being AMPLIFIED and converted to a larger one (used in blood clotting, however can be potentially disruptive)

Question 7

What is a feedforward control?

Answer 7

Anticipatory action which will alter behaviour before there is an ‘error’

Such as stopping eating before one is full
Increasing HR/ventillation starting exercise