Phylum Chordata Classification Urochordata Cephalochordata Vertebra Chordate evolution and the three phylum system pmc. Chordate evolution and the three phylum system journals.
Phylum Chordata Classification Urochordata Cephalochordata Vertebra Chordate chordate. Echinoderms are invertebrate marine animals that have pentaradial symmetry and a spiny body covering, a group that includes sea stars, sea urchins, and sea cucumbers. the most conspicuous and familiar members of chordata are vertebrates, but this phylum also includes two groups of invertebrate chordates. figure 29.2 deuterostome phylogeny. 29.1b: chordates and the evolution of vertebrates. Figure 29.1.4 29.1. 4: the lancelet, like all cephalochordates, has a head. adult lancelets retain the four key features of chordates: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post anal tail. water from the mouth enters the pharyngeal slits, which filter out food particles. the filtered water then collects in the atrium.
Comments are closed.