Chordates have endoskeleton characterized by flexible
rod (notocord) along back of embryo.
Muscles attach to rod providing flexible locomotion
Four features characterize chordates:
Single dorsal hollow nerve cor
Unique features of Echinoderms
Echinoderms exhibit secondary radial symmetry.
Are bilaterally symmetrical as larvae. Become radially
symmetrical as adults.
Adults possess five-part body plan (pentamerous
Worms that burrow in the ocean.
Have body with 3 regions: proboscis,
Most common species = acorn worms.
They are slow burrowers, using
the proboscis to burrow.