sea stars
True or false: sea stars have a minimum of 5 legs
True
how do amphibians reproduce?
external fertilization
are fish ectotherms?
yes!
what is the organ called that pumps water through the sea stars body?
madreporite
how long ago did amphibians evolve?
395 million years ago
what makes fish buoyant?
a swim bladder and oil filled liver
what phylum and class do sea stars belong to and what animals share a phylum with sea stars?
Phylum: echinoderms
Animals: brittle stars, sea cucumbers, sea urchin, sand dollars
why were vertebrates (amphibians) able to evolve from fish?
the fish they evolved from had a bony fin structure
name the key characteristic of a fish's body
notochord, dorsal, hollow nerve chord, postanal tail, pharyngeal slits,