Homeostasis

Homeostasis

1. Definition = constant internal, optimal function, feedback system

2. components

   • stimulus = produce change
   • receptor = detect
   • control centre = measures degree of change ie set point
   • effector = response

3. Positive Feedback ie enhance stimulus

   • Child birth
   • Breast feeding
   • Blood clotting

4. Negative Feedback ie reverse stimulus

   • body temp incr or decr
   • Blood glucose
   • Blood calcium

5. Impact of ageing on homeostasis

   • Homeostasis releases hormones as you age. Target organs become less responsive to the signals sent by the other organs.
     • Hormones that decrease with age are: aldosterone, calcitonin, growth hormone and renin
     • In woman: oestrogen and prolactin