Phylum Chordata. The chordates are a group of particular interest to us as we belong to it, being members of the subphylum Vertebrata.
These are the protostomes “mouth first” and deuterostomes “mouth second”.
(a solitary sea squirt)
Ascidian filter feeding process. Water is drawn
through the animal by the beating of cilia.
Branchial sac orpharynx