The phylum Chordata is a taxonomic group. All animals which have a  spine, or backbone, are classified in the phylum Chordata. There  are three subphylums in Chordata: Uroch â¦ ordata (tunicates),  Cephalachordata (lancelets), and Vertebrata (vertebrates).
The 12 vertebrae in the upper back make up what is known as the thoracic spine. They curve outward and inward to provide structure for the rib cage. The bones provide structure and flexibility for the body, while protecting the spinal colu... Read More.
1 Vertebrae in your thoracic spine connect to your ribs, making this part of your spine relatively stiff and stable. 2  Your thoracic spine doesn't move as much as the other regions of your spine, like the cervical spine. 3  The thoracic spine is supposed to have a kyphotic curve; it should curve inward.s you can tell just from the descriptions of curves, the spine is a complex thingâand we haven't even gotten to the various components of the spine. It's made up of many parts: vertebrae (bones), discs, ligaments, cartilage, tendons, blood vessels, nerves, the spinal cord, and muscles.