What is the role of the optic nerve in vision?

The optic nerve plays a crucial role in vision by transmitting visual impulses from the retina to the brain. Once light enters the eye, it is focused onto the retina, where photoreceptor cells convert the light rays into electrical signals. These signals are then carried by the optic nerve to the visual cortex of the brain, where they are processed and interpreted as images. This pathway is essential for the perception of visual information, making the optic nerve critical for sight.

The other roles mentioned, such as receiving light rays and regulating pupil size, are functions performed by different components of the eye, such as the cornea, lens, and iris. The optic nerve specifically does not block light; instead, it serves to relay the information captured after the light has been processed in the retina. Hence, the correct understanding of the optic nerve's function highlights its importance in connecting visual stimuli to the brain for interpretation.