Answers to Objectives
pp. 441. - Chordates- have pharynx which can function as digestive and respiratory. These organism have a notochord and are classified as deuterostomes. Echinoderms have spicules on their skin and they have exoskeletons made of calcium carbonate. - Phylum Chordata- have notochords and tubular dorsal nerve cords. They also have muscular tube obtained from mesoderms. Pharynx walls have gill slits and most of the organimsms have tails. Phylum Echinodermata-organisms that are unsegmented, bilateral in larvae and usually have a radial symmetry in adults. Phylum Hemichordata are also considered as the sisters of echinoderms and most of them have shorter ...
