deoxyribonucleic acid, desoxyribonucleic acid, DNA(noun) (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information.
But even adults don't often know what a notochord is. A notochord is a primitive beginning to the backbone. It appears in embryos as a small flexible rod made from cells from the mesoderm, which is one of the three layers of cells of embryos. Notochords are only found in the phylum chordata, a group of animals that includes humans.
A Chordate is a animal with a notochord. They do not need to have spines-they just need to have a spinal cord. Fish, Reptiles, Mammals, Birds, and Amphibians are all members â¦ of the Chordate phylum. There are also invertabrates closley related to these members of the Chordate phylum that are Chordates.t some point in their lives, a chordate will have a notochord, a nerve cord that runs down their back, and a slit in the throat area. The phylum name Chordata came from the n â¦ otochord, a flexible rod that supports the back. They include fishes, amphibians, and reptiles.