Biology 21, Developmental Biology, Take-home Final Exam (due 5/15/99)

Directions: Address both of the 100 point questions below in an essay of 2-5 double-spaced pages each. The essay should be clearly written and be free of grammatical mistakes. Strive to write professionally using the vocabulary of Developmental Biology. You may consult notes, books, journals, and online materials as you wish, but DO NOT consult with other people (including online discussion groups) in constructing your answers. Turn in this exam by sliding under the door of my office (Higley 301).

1. (100 points) Choose a topic of interest to you that we have covered in class, either in lectures by DM or in a group-led discussion. Pick an as yet unsolved problem relevant to the topic. Pose a hypothesis(es) to explain the problem, and proceed to devise an experiment or experimental approach that tests your hypothesis. The experiment(s) should be technically feasible! Describe the possible outcomes of the experiment(s) and your interpretation of the results in terms of testing the hypothesis of interest.

2. (100 points) Discuss the concept of "homology of process" in the context of two examples of your choice, one of which concerns the development of homologous structures (e.g. invertebrate and vertebrate nervous systems), and one of which concerns the development of analogous structures (e.g. bird and fly wing). In your discussion, be sure to be specific about the molecules that illustrate the concept of homologous processes.