Vertebrate Physiology 437 EXAM II NAME, Section (circle): am 21 October Exam is worth 100 points. You have 75 minutes.

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1 Vertebrate Physiology 437 EXAM II NAME, Section (circle): am 21 October Exam is worth 100 points. You have 75 minutes. pm True or False (write true or false ; 10 points total; 1 point each) 1. Calsequestrin is typically found in the plasma membrane and aids in the sequestration of calcium. 2. Type I skeletal muscle fibers have a smaller diameter and a higher density of mitochondria than Type IIb fibers. 3. The latch state of smooth muscle can produce force with less ATP than striated muscle would require. 4. A kinase phosphorylates a protein. 5. Injections of arginine vasotocin (AVT) causes male cricket frogs to call more frequently. 6. Paracrine hormonal activity means that a hormone acts directly on the cell that released it. 7. Follicle stimulating hormone (FSH) and thyroid stimulating hormone (TSH) are both released from the anterior pituitary. 8. Andre the Giant was afflicted with a thyroid condition that led to his enormous size. 9. The I-band becomes shorter during sarcomere shortening. 10. Skeletal muscle develops the most power at the maximum muscle shortening velocity. Shortest Answer (2.5 points each, 25 points total; ~a few words). 1. List two potential benefits of intermittent locomotion? 2. Late in the luteal phase, what helps maintain the corpus luteum in the event of egg fertilization? (also detected in 'rabbit pregnancy test') 3. What are two take-home messages from the Miyazawa et al. paper (2003) that reiterate issues also discussed in lecture? 4. What are the two most obvious short-term uses of ATP in muscular contraction? 5. List three typical sources of ATP for skeletal muscle contraction.

2 Page 2 of 6 6. Distinguish between catecholamines and glucocorticoids and give an example of each. 7. How can the same chemical substance be both a hormone and a neurotransmitter? 8. How are release of hormones and neurotransmitters functionally similar? 9. Give two examples of common 2 nd messengers used in intracellular signalling. 10. What effect does glucagon have on the liver and on blood glucose concentration? Short Answer (4 points each, 36 points total; ~a sentence or two). 1. At the level of an individual sarcomere, draw the length-tension curve and label the axes appropriately. Why does the length-tension curve for skeletal muscle have the shape that it does? 2. Draw a positive work loop with appropriately labelled axes.

3 Page 3 of 6 3. How do birth control pills work? 4. Describe two ways skeletal muscle can increase force production. Is increased force production in cardiac muscle different? 5. Answer a or b (circle the letter of the question you are answering): a) What role does progesterone play in the mammalian estrous cycle? b) Explain the marvelous adaptive radiation of placental mammals (vs. marsupials) in relation to progesterone. 6. How does abuse of exogenous testosterone by weightlifters reduce their sperm count? 7. Briefly describe how insulin activity is altered in Type I and Type II Diabetes. 8. List two of the three ways that muscle fatigue and inorganic phosphate (P i ) concentration may be mechanistically linked.

4 Page 4 of 6 9. Describe the mechanism of activity of a typical steroid hormone. Long Answer (6 points each, 18 points total; ~a paragraph or diagram). 1. Diagram (using boxes and arrows) the stress response pathway beginning with the stress as detected by the hypothalamus. Include the relevant organs, glands, and hormones. 2. Draw a schematic map of the cells in the retina that eventually send signals to the brain via the optic nerve. Label the 5 different cell types and indicate how lateral inhibition could be achieved.

5 Page 5 of 6 3. Describe the patellar tendon reflex. Include discussion of afferent signals, efferent signals, stretch receptors, antagonistic muscles, divergence and convergence, etc. (Use the following incomplete drawing of an antagonistic muscle pair and the relevant joint to jog your memory as to the important events and structures.)

6 Page 6 of 6 Longer Essay Answer (11 pts; ~a few well-organized paragraphs). 1. Describe excitation-contraction coupling in vertebrate skeletal muscle. Begin with the action potential moving along the axon of an alpha motor neuron.