Chordates Research Paper

The Chordata is the third largest phylum in the kingdom Animalia. Chordates are bilaterally symmetrical; meaning one half of their body is a reflection of the other half. The Chordata phylum has several general characteristics unique to only this organization of creatures. The first is pharyngeal slits, which are openings behind the head that connect to the throat. These are known as gills in some chordates. Humans have these in the womb but eventually form into the inner ear. The second feature is a notochord, which is used to support the nerve cord. The third feature is a dorsal nerve cord, which is a bundle of nerve fibers that connect the brain to all other organs and muscles of the body. The fourth feature is a post-anal tail. This is another feature that humans outgrow in the womb. The final feature of Chordates is that their blood is contained in …show more content…
The classes Myxini and Hyperoartia only have one creature per class, the former being hagfish and the latter being lampreys. The class Myxiniare found anywhere from the depths of the sea to the shallowest areas of the oceans. The Hyperaortia originated in the Atlantic Ocean and have migrated to the Great Lakes. The next class, Placodermi, are an extinct group of armored fish. The class Chrondrichthyes are cartilaginous fish found alongside the class, Actinopterygii, otherwise known as the bony fish, in various aquatic environments. The next several classes are more well known in basic science classes. Class Amphibia are amphibians known as the first creature to have limbs and now are commonly live near water. Class Reptilia evolved from the class Amphibia during the Carboniferous period and now primarily reside in warm dry climates. Classes Aves and Mammilia both evolved from the class Reptilia during the Jurassic period and now reside in a diverse environments ranging from mountains to