The retina, inside the eye, contains a light-sensitive membranous layer of cells. These are specialized nerve cells: elongated rods (flower like shapes) and cone-tipped cells, that produce vision. The browne structure at bottom represents the epithelium. The rods are very sensitive and respond to dim light. With them the eye can detect images. While the cones are less sensitive but responsible for colour vision. Rods and cones pass visual signals through the optic nerve to the brain. Spectral colors above the cells represents light coming through the iris of the eye.