Chordates

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Comparative Anatomy Lab One

Abstract:

This laboratory is to understand the classification and comparison of chordates.

Introduction:

In this lab manual it shows the structure of phylum Chordata, subphylum Vertebrata. The objective is to observe the major body systems and track its course of evolution from the start of the system to its presence in animals alive today. Also it is to discuss how these systems work together to produce life.

The main topic to focus in this lab is the Chordates, which are group of animals that includes the vertebrates under the phylum Chordata. They are united by having a notochord, a hollow dorsal nerve cord, pharyngeal slits, an endostyle, and a muscular tail extending past the anus.

Species: Yellowfin tuna

Materials: Lab manual

Discussion:

The phylum Chordata is broken down into three subphyla: Vertebrata,Urochordata and Cephalochordata. Urochordate larvae have a notochord and a nerve cord but they are lost in adulthood.

Cephalochordates have a notochord and a nerve cord but no vertebrae. In vertebrates, the notochord has been replaced by a bony vertebrae.

The chordates and two sister phyla, the hemichordates and the echinoderms, make up the deuterostomes, a superphylum. The extant groups of chordates and the major metozoan groups are shown in the phylogenetic tree in the lab manual.