BIOL 412 Taxonomy

Porifera

sponges

- no true tissue

- have specialized cells

- pores allow water to enter

Cnidarian

jellyfish, coral

- interior gut cavity for digestion

- main body forms: polyps or medusae

- stinging cells to capture prey

Platyhelminthes

flatworms

- ciliated cells on underside for movement

- single opening for digestive cavity

Nematoda

roundworms

- body cavity

Mollusca

snails, clams, squid

- one of the largest

Annelida

segmented worms - earthworms, leeches

Arthropods

insects, crustaceans

- largest phylum

- exoskeleton made of chitin

- open circulatory system

- segmented body

Echinodermata

urchins, sea star

- endoskeleton

Chordata

most vertebrates

Levels of Multicellularity

tissues, bilateral symmetry, body cavity, coelom, endoskeleton