Final Exam Biology 326 Fall 2009 Name:_____________________________

1. (3) How is fatigue defined for a muscle?

2. (6) Draw a length tension curve for a sarcomere.

3. (8) Compare the properties of a isometric and an isotonic contraction in muscle fibers. Explain the differences in the latent period mechanistically.

4. (4) Where is the flow rate slowest in a closed circulation and why is this the case (mechanistically not why it assists in exchange of nutrients).

5. (12) ON THE BACK OF THIS PAGE: In striated muscle describe the process of excitation-contraction coupling - include molecules and structures and what is happening.

6. (5) Give the Poiseulle Equation and then describe the factor(s) which are most important in determining blood flow under normal circumstances.

7. (8) Diagram a typical normal pacemaker potential over time and then show how it changes when heart rate slows.

8. (4) What is the difference in the structure of the microcirculation in animals with closed and open circulatory systems?

9. (6) In what part of the circulation is gravity often a determining factor of flow. What adaptations exist to counterbalance this potential problem.

10. (4) Why does the Right-to-Left shunting of blood take place in the fetal circulation

11. (6) Tell me why marine sharks are not considered osmoconformers?

12. (4) The saturation deficit decreases during the warm summer months in Washington D.C.. What are the implications of this?

13. (6) If I have determined the U/P and relative clearance of a material what might I be able to conclude from this information?

14. (4) An animal excretes 1 mole of ammonia and 1 mole of urea an hour. Is this an ammonitelic or ureaotelic organism. Give me the reason for your answer.

15. (6) Where does countercurrent exchange and counter current multiplication take place in the nephron?

16. (14)ON THE BACK OF THIS PAGE. How are passive and active reabsorption related? In your answer include the role of ADH and aldosterone affect reabsorption of different kinds in the nephron.