Page 1 of 3The University of Melbourne Semester 2 Assessment 2010 Department of Zoology Subject: COMPARATIVE ANIMAL PHYSIOLOGY (654-218; ZOOL20006) Student Number: 149 Reading Time: 15 minutes Writing Time: 2 hours This paper has 3 pages in total. Authorised Materials: no materials are authorised Instructions to invigilators: Students require script books only. Instructions to students: Answer ALL Section A questions in one script book. In a separate script book: Answer FOUR questions from Section B. Answer TWO questions from Section C. You must complete all three sections. All answers should be written in the script books and not on the examination paper. DO NOT REMOVE EXAMINATION PAPER FROM THE EXAMINATION ROOMPage 2 of 3Section A. Answer ALL questions (total 20 marks, allow 20 minutes) One mark questions: 1. Define acclimatization. (1 mark) 2. What is a hydrophilic chemical messenger? Give an example. (1 mark) 3. How does hemolymph re-enter an insect’s open circulatory system? (1 mark) 4. What is meant by the term “facultative endotherm”? (1 mark) Two mark questions: 5. How does an exocrine gland differ from an endocrine gland? (2 marks) 6. Describe how the permeability of the kidney collecting duct is regulated in amphibians. (2 marks) 7. Which division of the autonomic nervous system is largely responsible for regulation of blood vessel tone and which transmitter is used by the postganglionic neuron? (2 marks) 8. Name TWO reasons why air is a better respiratory medium than water. (2 marks) 9. What is the Bohr effect and how does this affect gaseous exchange at the respiratory exchange surface? (2 marks) 10. Describe the process of non-shivering thermogenesis. (2 marks) 11. What is parthenogenesis and name ONE advantage of reproducing in this way? (2 marks) 12. What are endocrine disrupting chemicals and how do they affect reproduction? (2 marks) Section B: answer only FOUR questions (5 marks each, allow 10 minutes each, total 20 marks) You need to provide 5 different points (each worth 1 mark) to obtain 5 marks. 1. What are the similarities and differences between a neurosecretory cell and an endocrine cell? (5 marks, 10 minutes) 2. Describe the rapid response to stress. (5 marks, 10 minutes) 3. Outline the osmoregulatory processes in an elasmobranch. (5 marks, 10 minutes) 4. Describe the ion channels and the direction of ion movement that are involved in the action potential in an axon. What is the significance of the threshold potential for this process? (5 marks, 10 minutes) 5. How does metabolic rate scale with size in endotherms and ectotherms? What are some explanations for this pattern? (5 marks, 10 minutes) 6. Explain the effects of oestrogen on the ovary and uterus during oestrus. (5 marks, 10 minutes)Page 3 of 3Section C: answer TWO questions (10 marks, allow 30 minutes EACH, total 20 marks) 1. Broadly discuss the physiological and behavioural mechanisms used by desert endotherms and ectotherms for conserving energy and water. (use examples to illustrate your points). (10 marks) Answer both parts of the question 2. (i) Describe the respiratory system and mechanisms of ventilation in a marine mammal. (6 marks) (ii) How do diving mammals overcome periods of hypoxia during a dive? (4 marks) 3. Describe the circuit of the baroreceptor reflex and outline its role in the response to the postural changes that occur when going from lying down to standing up (10 marks) Answer both parts of the question 4. (i) Outline the constraints on herbivore digestion. (2 marks) (ii) How does the structure of the digestive system and digestive processes of a vertebrate carnivore differ from that of a vertebrate herbivore? (use examples to illustrate your points). (8 marks) END OF