Explain in detail about the optic nerve
The optic nerve contains more than one million axons that initiate in the ganglion cell layer of the retina. This structure originatcs at the back of the eye just above and medial to the posteiior pole. It contiilues on from the retinal nerve fibre layer. The optic nerve consists of visual fibres and pupillonlotus Iibres (for pupills~ry reflex and oculm movements). Fibres frbm peripheral retina lie deeper in retina but occupy the most supelficial pm-t of optic nerve while those from central retina are superficial in retina but centrally placed in the optic nerve.