Biology of Fishes, Mid-term Examination, Fall 2004
Below are 6 questions. Choose 5 and answer them in a 1.5 pages or less. Concise language and succinct explanations will be highly valued.
1. Describe the osmotic problems faced by fishes migrating from fresh water to salt water and in fishes migrating from saltwater to freshwater. Describe the physiological adjustments you would expect to observe under each scenario.
2. Discuss the physiological importance of countercurrent exchange systems in fishes.
3. Contrast the respiration, buoyancy regulation, and swimming modes used by coral reef fishes (e.g., pufferfish) with those used by pelagic fishes (e.g., tuna).
4. Major changes in the trophic apparatus have occurred in the diversification of actinopterygians. Discuss these changes with emphasis on the oral and pharyngeal jaws.
5. Bioelectrogenesis is an important part of the biology of numerous aquatic gnathostomes. Discuss the functions of that process in two different gnathostome clades.
6. The phylogenetic relationships of gnathostomes were a focus of much of the early lectures in this class. Below is a list of some of these groups. List the evolutionary novelties that document their existence.