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Study Questions:
1. What are the stages of animal embryogenesis?
2. Distinguish "protostome" and "deuterostome".
3. Why are "goofy" characteristics like whether the blastopore forms the mouth or anus used to reconstruct phylogenies? Explain in terms of the three reasons why organisms might share a characteristic.
4. Draw the cell layers in a sponge and describe the function of each.
5. What are the two body types seen in Cnidarians?
6. List four groups of Cnidarians.
7. How do Cnidarians feed?
8. Why is bilateral symmetry, rather than radial symmetry, associated with "cephalization" in motile organisms?
9. Why are sedentary bilateral organisms "decephalized"?
10. How doe Planaria feed and distribute nutrients through their tissues?
11. What is a lophophore? What is a trochophore?
12. Provide a hypothesis for the increase in animal fossils 500 mya.