Homeostasis

1
Homeostasis

• Positive and negative feedback

2
Negative feedback
3
Negative feedback

• Cancels or counteracts original stimulus
• RECEPTOR (e.g., skin thermoreceptors) Registers
  that body is too hot
• INPUT (sensory neuron impulse to the Integrator)
• INTEGRATOR (brain --- hypothalamus)
• OUTPUT (motor neuron impulse to the Effector)
• EFFECTOR (sweat glands)

4
Positive feedback
5
Positive feedback

• increases original stimulus

6
In positive feedback

• A change is detected by receptors
• Information is transmitted to control center.
• Control center activates effectors
• Effectors generate a response which increases the
  stimulus
• Thus, positive feedback acts to reinforce or
  strengthen the stimulus or change.