| A | B |
|---|
| gastropod | stomach-footed mollusks |
| radula | tongue like organ within the mouth of a gastropod and used to scrape, grate, of cut food |
| open circulatroy system | blood moves through vessesl and into open spaces around the body organs |
| nephridia | organs that remove metabolic waste. Mollusks are the first animals to evolve these structuress |
| filter feeders | main difference between gastropods and bivalves |
| Cephalopoda | class of mollusks with a closed circulatory system |
| closed circulatory system | circulatory system in which blood in entirely enclosd in a series of blood vessels |
| gizzard | a sac with muscular walls and hard particles that grind food before it passes into the intestines. |
| arthropod | invertebrate with bilateral symmetry, a coelom, an exoskeleton, and jointed appendages |
| molting | process of shedding the exoskelton in arthropods or the feathers in birds |
| cephalothorax | fused head and thorax of an arthropod |
| water vascular system | system unique to enchinoderms that enables them to move, exchange gases, feed, and excrete waste |
| chordates | animals with a notochord, dorsal nerve cord, and gill slits |
| echinoderms | starfish, brittle stars, sand dollars, sea urchins |
| examples of arhropods | spiders, insects, crustaceans |
| annelids | leeches, bristleworms, earthworms |
