1. Comparative Vertebrate Physiology Homeostasis

2. Course Outline Systems Nervous, Muscular, Circulatory, Respiratory, Osmoregulatory, Digestive, Reproductive Processes Thermoregulation Metabolism

3. Course content Structure - what does it look like? Function- how does it work? How and Why? The comparative approach

4. Homeostasis

5. Claude Bernard’s concept All organs interact All cells of organs bathed in internal fluid Cells exist if fluid remains constant in quantity and quality - quality affects quantity Fluctuations occur within narrow limits

6. Feedback mechanisms Control system Sensor Set point adjustment Disturbance Error signal Inverted amplifier Negative feedback -

7. Beneficial - Example: perspiration Doesn’t prevent displacement Restores stability close to operating parameters

8. Feedback mechanisms Control system Sensor Disturbance Signal Amplifier Positive feedback Output +

9. Positive feedback Rare and mostly destructive e.g. congestive heart failure Some are beneficial e.g. vomiting

10. Control systems Integration (CNS) Stimulus Response Effector (muscle, gland) Receptor (cell) AfferentEfferent