Figure 21-100

   The neural map from eye to brain in a young zebrafish

(A) Diagrammatic view, looking down on the top of the head. (B) Fluorescence micrograph. Fluorescent tracer dyes have been injected into each eye—red into the anterior part, green into the posterior part. The tracer molecules have been taken up by the neurons in the retina and carried along their axons, revealing the paths they take to the optic tectum in the brain and the map that they form there. (Courtesy of Chi-Bin Chien, from D.H. Sanes, T.A. Reh, and W.A. Harris, Development of the Nervous System. San Diego, CA: Academic Press, 2000.)