1. Bell Ringer: 1.The calves are _______ to the shin. 2.Which plane divides the body into R/L surfaces? 3.Body cavity that includes the chest 4.Body cavity that includes the brain 5.Body region anterior side of skull above forehead 6.Body region that is the heel of foot 7.Body region that is the superior boney structure thingy part of the shoulder 8.Body region that is just inferior to the navel 9.Body region posterior to the knee

2. Joke of the Day: Teenager (noun) – someone who is well prepared for a zombie apocalypse but not ready for tomorrow’s Anatomy test.

3. Joke of the Day:

4. Homeostasis

5. Homeostasis Introduction You are exposed to ever changing environmental conditions. For example, you may walk out of an air conditioned room into the hot summer sun. However the cells in your body work best when their surroundings are kept constant. Your body has many mechanisms that keep the cells surroundings constant even though your external environment is changing. This is homeostasis. Homeostasis is very important because when it fails you become ill and may die.

6. Homeostasis Definition: Maintaining a stable internal environment. Examples: Body Temp Blood Pressure Blood CO2 levels Glycogen levels Etc… Homeo – SameStasis - Standing Homeostatic Imbalance: A disturbance in homeostasis resulting in disease

7. Homeostatic Controls All homeostatic control mechanisms have at components: – Receptor – Control Center – Effector

8. Receptor: Detects “problem or change”

9. Afferent Pathway : Takes “problem” to Control Center

10. Control Center: Analyzes info., makes a decision

11. Efferent Pathway: Takes “decision” to effector

12. Effector: Carries out instructions, causes change

13. Positive Feedback: - T he rise in one variable causes a rise in the next -Body is trying to increase the stimulus -Less common Positive Feedback + + StimulusResponse Example: Blood clotting and birthing

14. Negative Feedback: - T he rise in one variable causes a fall in the next -The body is trying to slow or stop the stimulus -Most common in body Stimulus Response Example: Body temp, blood pressure, hunger and metabolism, household thermostat

16. Negative Feedback Loop