What is the role of the optic nerve?

The optic nerve plays a crucial role in the visual system by transmitting visual information from the retina to the brain. When light enters the eye, it is focused on the retina, where photoreceptor cells convert the light into electrical signals. These signals are then carried by the optic nerve to various parts of the brain, particularly the visual cortex, where they are processed and interpreted as images. This function is essential for vision, as it allows the brain to receive and make sense of visual stimuli.

The other options misrepresent the functions associated with the eye. For example, regulating eye pressure is primarily the role of the aqueous humor and various drainage systems within the eye, such as the trabecular meshwork. Protecting the retina from injury involves physical structures such as the sclera and the bone surrounding the eye, rather than a specific role of the optic nerve. Focusing light onto the lens is the function of the cornea and lens themselves, and not the optic nerve, which is solely responsible for transmitting signals after the light has been processed by the retina.