1. PED 105: ANATOMY & PHYSIOLOGY I Barbara J. Engebretsen Assistant Professor, HPLS

2. Terminology Anatomy Physiology

3. STRUCTURE & FUNCTION “Design & Job” “Wings” “Scaffolding” “Molecular Motors”

4. HOMEOSTASIS  Maintaining Life and Health demands an ability to respond to constant disruptions of our internal environment  The Goal of Homeostasis is to maintain a constant internal environment

5. HOMEOSTASIS Healthy Balance “Set Point” Negative feedback

6. QUESTIONS: What is our “internal environment”? What are some conditions of that environment that must be regulated and maintained?

7. ANSWERS: Water!! A 70 kg adult is about 41 liters of H 2 O: ~8-9% of our body weight

9. Watery Conditions: Key Variables Temperature pH (H + and OH - ) O 2 /CO 2 Solutes: NaCl, K+, Ca++... Nutrients

10. And More... Waste Products Volume Compartment

11. Key Terms: Homeostasis Set Point Negative Feedback Sensor (Receptor) Control Center (911!) Signal Transduction Effector

12. Another Question: After donating blood, what do you predict will happen to heart rate? WHY?

13. Think about: What is the “set point” condition? What are the “receptors”? What is the control center? What is the “effector”? This is Negative Feedback!

14. What if the negative feedback sequences FAIL to return blood pressure to normal? This is BAD: Hypovolemic Shock is a failure of Negative Feedback. Shock is Fatal.

15. Pathology: Disease Failure of Negative Feedback or worse: Positive Feedback Positive Feedback exceptions: parturition, ovulation

16. Homeostasis Lab: Take 10: Read the Lab Record you pulse: Sit quietly, recording HR for 15 seconds. Wait 15 seconds, then repeat Take 10 readings Multiply your HR by 4 to get minute heart rates

17. Calculations: Calculate your average HR: round off to whole number Graph your average by drawing a red line at that value Plot each of your readings on the graph

18. Advanced Thinking: Calculate the Standard Deviation of your average HR How “tightly” is your HR controlled? Find out that average HR for exercisers vs. non-exercisers Did our data match your hypothesis?

19. Summary Define Anatomy/Physiology Structure/Function Relationships Homeostasis: Negative and Positive Feedback

20. Assignment: Read: Chapter 1:1-9 Outline sturctural/functional organization (p. 2-3) Turn in Homeostasis lab