1 2 3 4 5

		In addition,the development of somites in a 24 hour old zebrafish will also be examined. Somites give rise to the cells that form the vertebrae,ribs and the skeletal muscles of the back. They determine the migration pathways of neural crest cells and spinal nerve axons. They first appear in the anterior portion of the trunk,and form as a function of the developmental rate of the embryo. Therefore,it is possible to use the number of somites present to gauge how far the embryo has developed. To examine how thoroughly the motor neurons and somites have developed by the 24 hour stage,the technique of whole mount antibody staining will be used. The ZNP-1 antibody will specifically bind to the primary motor neurons. Since ZNP-1 will not bind to the somites, another antibody,F6,will be used to bind to the somite boundaries. The ZNP-1 and F6 treated embryos will be treated with a secondary antibody, Fluorescent Goat anti-mouse IgG, so that the stained neurons and somites can be observed under a fluorescent microscope.