1. Feedback System How does the body sense, process and respond to changes in body conditions? http://www.youtube.com/watch?v=CLv3SkF_Eag

2. Changes Changes in internal and external environments can lead tounbalancedconditions which leads to illness.

3. sense Receptors in different organs sense the change…

4. process The endocrine and nervous systems process the information…

5. hormones neurotransmitters and send out signals called hormones and neurotransmitters…

6. respond … causing other organs to respond to the change…

7. … to restore homeostasis!

8. Feedback System System that monitors the output and uses it to adjust the input.

9. Sense (Sensor) Control Center Respond (Effector)

10. Three parts of a feedback system: 1.SENSOR - detects the change 2.CONTROL CENTER- receives info from sensor, processes info and sends a signal to the effector 3.EFFECTOR – responds by changing its activity

11. Feedback loops can be negative or positive.

12. negative Most body systems use negative feedback.

13. reverse Body responds to reverse the direction of change (bring it back to the set point)

14. The Thermostat Analogy

15. The Body’s Thermostat Body Temperature Nerve Receptors BrainMuscles

16. Positive feedback is also possible. (But does NOT result in balance)

17. amplifies response to a change pushes the variable even more in the same direction (amplifies the change)

18. Room Temperature ThermometerThermostatFurnace

19. rapid change Positive feedback used when rapid change is desirable.

20. Environment