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Zoology 432 Invertebrate Zoology Exam I
Name ________________________
1. Which animal phylum contains the highest number of described species? 2
Arthropoda
2. What are characteristics of Protista and Animal Kingdoms? 5
Protista: unicellular, no tissues, eukaryote
Animalia: multicellular, tissues, eukaryote
2. Why is the Cambrian geological stratum of importance to the study of diversity? 5
Many extant phyla first appear; huge radiations of new taxa; high diversity in forms
3. What are two phyla that appear before the Cambrian (in the Precambrian)? 3
Porifera, Cnidaria
4. What are five phyla that appear during the Cambrian? 5
Mollusca, Brachiopoda, Ctenophora, Priapulida, Onychophora, Arthropoda, Phoronida,
Annelida, Echinodermata, Chordata, Hemichordata, Tardigrada, Nematoda, Nemertina,
Platyhelminthes, Rotifera, Nematomorpha
5. What is the International Code of Zoological Nomenclature? 5
Process for describing and naming of organisms. Includes Genus species epithet, describer name
associated with species name, type specimen in museum
6. Why are taxonomic arrangements different from evolutionary arrangements based on
molecular information? 5
Taxonomic arrangements are based on morphology or other appearance characters that can be
examples of convergent evolution. Molecular information is considered to be more reliable for
avoiding convergence.
7. What evolutionary characters were important in the early diversification of life? Explain why
they were likely important. 5
Flexible architecture of genetic regulation: developmental pathways can be changed rapidly with
simple gene differences, and result in major differences in body plans. E.g., Hox genes.
8. What is a deuterostome and a protostome? 5
Deuterostome = first opening in developing embryo will be anus
Protostome = first opening in developing embryo will be mouth
9. Why was there such high diversity in animals following the Cambrian explosion? 5
Flexible architecture of genetic regulation: same answer as 7
10. What are the classes in Porifera? 5
Demospongiae, Calcarea, Hexactinellida
11. What are distinguishing characters of the classes of Porifera? 5
Calcarea: spicules are calcium carbonate
Hexactinellida: spicules are silica
Demospongiae: spicules spongin or silica
12. What are the characteristics and an example in the phylum Euglenida? 5
2
Flagellate Protistan, mostly freshwater, habitat w/decaying organic matter
13. What are the characteristics and an example in the phylum Cnidaria? 5
Nevermind
14. What are the characteristics and an example in the phylum Dinoflagellata? 5
Unicellular, few are colonial, produce toxins, flagellates, Noctiluca, Ceratium, Red tide
15. What are the characteristics and an example in the phylum Rhizopoda? 5
Pseudopodia, amebas, mostly free-living, some parasitic, Entamoeba histolytica, Difflugia
16. What are the characteristics and an example in the phylum Diplomonida? 5
Plasma membrane rigid from three microtubular roots, most phagotrophic feed on bacteria,
asexual cyst-forming Protistan, Giardia
17. What are the characteristics and an example in the phylum Amoebozoa (Lobosea)? 5
Same as 15
18. What are the characteristics and an example in the phylum Chlorophyta? 5
Plant-like Protistans: chloroplasts, unicellular, some colonial, Volvox
19. Sketch a diagram of the life cycle of Trypanosoma. Describe your sketch. 8
20. Sketch a diagram of the life cycle of Giardia on the back. Describe your sketch.7