1. Describe the different types of symmetry.
Asymmetry: no particular pattern to body shape
Radial symmetry: Body organized circularly; similar to a wheel
Bilateral symmetry: Definite right and left halves; humans have bilateral symmetry
2. What are the differences between protostomes and deuterostomes?
Protostomes: Blastopore becomes mouth; ventral nerve cord ; spinal cleavage
Deuterostomes: Blastopore becomes anus; dorsal nerve cord; radial cleavage
3. What animals are in each of the following phyla? What characteristics are unique to each phyla?
A. porifera: sponges; no symmetry; no tissue; filter food particles from water
B. cnidaria: Jellyfish, corals, sea anemones; radial symmetry; tissues; stinging tentacles; olyp has mouth directed upward; Medusa has mouth directed downward
C. mollusca: Snails, clams, oysters, squid, octopus; all have a mantle, a visceral mass, and a foot
D. annelida: segmented worms; earthworms, leeches; body segments repeated along length of body
E. platyhelminthes: Flatworms; planaria, tapeworms; flat body; no body cavity
F. nematoda: Roundworms; non-segmented body; some are parasites
G. arthropoda: Exoskeleton; jointed appendages; segmented body; crustaceans; crabs, shrimp, lobsters, crayfish
H. Echinodermata: Starfish; deuterostomes, water vascular system; radial symmetry in adult; bilateral symmetry in larva
1. Define endothermic and ectothermic. Which vertebrates are endothermic? Which vertebrates are ectothermic?
Ectothermic: Body temperature stays relatively the same as the environment; Amphibians, reptiles, fish
Endothermic: Internal way to control body temperature; Birds, mammals
2. Define monotreme and marsupial.
Monotreme: Mammals that lay eggs; includes duck-billed platypus and spiny anteater
Marsupial: Mammals with pouches; young born very immature; complete development in mothers pouch, where mammary glands are located; includes kangaroos, koalas, and opossums
3. List the characteristics of all chordates.
Deuterostomes; postnatal tail; notochord; dorsal tubular nerve cord; pharyngeal pouches