BIO 101 Case 3 Assignment: Principles of Taxonomy

      Principles of Taxonomy Name BIO 101 Case 3 Trident International University Date     Part I: Sea squirt

1. List the Kingdom and Phylum, for the sea squirt and then briefly describe the characteristics that determine the organism's classification at each taxonomic level. 

The sea squirt belongs to the kingdom Metazoa (animals) the phylum Chordata and the subphylum Urochordata (Guralnick et al, 2014) Kingdom Metazoa characteristics 

• They are eukaryotic
• They do not make their own food and depends on the other organisms for food (depend on animals and plants)
• Their habitat is the sea
• There are multicellular
• They have the ability to move

Chordate characteristics Guralnick, Waggoner, Speer & Smith highlight the common features among chordates have the Pharyngeal slits – “a series of openings that connect the inside of the throat to the outside of the "neck". These are often, but not always, used as gills” Dorsal nerve cord - a “bundle of nerve fibers which runs down the "back". It connects the brain with the lateral muscles and other organs.” Notochord – “cartilaginous rod running underneath, and supporting, the nerve cord,” and the sea squirt has the notochord (primitive backbone) at the larval stage Post-anal tail – “an extension of the body past the anal opening.”    

1. Why is the sea squirt classified in the same phylum as a sea otter?

            The sea squirt and sea otter are classified as chordates and share similar features during development including the presence of the notochord during the early stages of development. Even as the sea squirts (tunicates) have sack like bodies they have a nerve cord running along the top of the body, and the sea otter also have dorsally placed nerve chord during development. 3 Click on the "Life History & Ecology" tab to read more about Urochordates.  What is another name that is used to describe them?  Briefly describe the adult versus larval phase of its life cycle.              The Urochordates / tunicates or sea squirts belong to a marine group of animals and the larva resembles the tadpole and is able to swim with the aid of a tail (Guralnick et al, 2014). However, as the larva matures it metamorphoses into an adult it becomes more sedentary after losing its tail and the ability to move and has fewer features with the other chordates at the stage of development (Guralnick et al, 2014). The nervous system also disintegrates with the adult now resembling a sack and ha two siphons where water enters and exits, with the water being filtered to procure food. At times reproduction is asexual through budding or maybe sexual, including possessing both female and male organs as a hermaphroditic organism (Guralnick et al, 2014). Pa...