9. Phylum Chordata – The Chordates: fish, reptiles, amphibians, birds, mammals
a.) Habitat: marine, freshwater, or terrestrial
b.) Symmetry: bilateral
c.) Dorsal nerve cord.
d.) Chordates have a flexible, supporting rod or notochord on their dorsal side. In the invertebrates the
notochord remains stiff and flexible. In the vertebrates, cartilage or bone replaces the notochord to form a
supporting backbone.