False-colour scanning electron micrograph (SEM) of rod and cone cells of the eye retina. Cone cells (blue) and more numerous rod cells (pink, purple) are specialized light-sensitive cells. They occur on the surface of the retina. They are responsible for detecting visible images, which are transmit- ted as nerve impulses to the optic nerve and the brain. There are about 130 million rod cells in the human retina; they detect light intensity and so are important for day and night vision. While the less numerous cone-like cone cells (about 6.5 million in the human retina) respond specifically to colour. Magnification: x730 at 6x7cm size. Magnification: x1120 at 4x5 inch size.
(Source: sciencephoto.com)









