Phylum _____ includes both vertebrate & invertebrate animals.
The 2 groups of INVERTEBRATE or nonvertebrate chordates are _____ & _____.
All chordates have, at some stage in their lives
"Dorsal, hollow nerve cord"; notocord; pharyngeal pouches; tail
Describe what happens to each of the above as the animal develops.
The "dorsall, hollow nerve cord" gives rise to the nervous system. The notocord is replaced by bone in many. Pharyngeal pouches give rise to gills in fish (lungs). Tail often dissapears during embryonic development or stays a tail.