INSTRUCTIONS: Answer all of the following questions. Many answers require only a word or two, while others will need a few sentences. Beside each question is the worth of the answer in points. The points add up to 102, although you need only score 100 to get full credit. Please budget your time according to the points (about a half-minute per point).

1. [4] Compare alternation of generations in the three classes of Cnidarians.
2. [3] Why are sponges classified as Parazoa instead of Eumetazoa?
3. [4] Briefly describe the path followed by a sperm entering a typical sponge.
4. [2] List two apomorphies of sponges.
5. [3] What distinguishes a homeotic gene from other genes?
6. [3] How might you distinguish between a hydrozoan and a scyphozoan medusa?
7. [3] What is a clade?
8. [4] Distinguish between monophyletic, paraphyletic, and polyphyletic groups
9. [3] How are gene (or protein or rRNA) sequences used to date divergence of animal taxa?
10. [3] List the major ICZN taxonomic categories.
11. [24] In a sentence or two, differentiate between:
    • Pharynx and mouth
    • Definitive and intermediate host (for a parasite)
    • spiral and radial cleavage
    • Cladistics and classical taxonomy
    • asconoid, syconoid, and leuconoid body types in sponges.
    • diploblastic and triploblastic organisms
    • radial and bilateral symmetry
    • hermaphroditic and gonochoristic animals
12. [4] Why are animals with an asexual phase in their life cycle (e.g., Cnidaria) more likely to evolve rapidly?
13. [3] In what way does the gut of a turbellarian make up for the lack of a coelom?
14. [3] What does a flame cell do?
15. [12] Complete the following table:

    Common Name	Phylum	Class
    Venus' girdle
    commercial sponge
    hookworm
    planarian
    tapeworm
    reef coral

16. [3] Why is a nerve net an advantage for medusae?
17. [2] What is the function of the vellum in hydrozoan medusae?
18. [2] What is a scyphistoma?
19. [2] What is eutely?
20. [2] Which class of Platyhelminthes is a free-living flatworm most likely to belong to?
21. [5] Using the letters a through e, place in life-cycle order the following stages in the life cycle of a digenic fluke:
    • _____ metacercaria
    • _____ redia
    • _____ sporocyst
    • _____ cercaria
    • _____ miricidium
22. [2] What is a gemmule?
23. [2] What is so significant about the fossils found in the Guizhou phosphorus deposits in China?
24. [2] What is a syncytium? Give two instances in which we saw syncytia.
25. [2] What is an axoblast?
26. [0] What is your favorite parasite, and why?