Which retinal cells form the optic nerve?

Which retinal cells form the optic nerve?

• A. Retinal ganglion cells.
• B. Photoreceptors.
• C. Horizontal cells.
• D. Amacrine cells.

Answer: (A)

The part of the retina that carries signals out to the brain is the retinal ganglion cells. Their axons bundle together at the optic disc and form the optic nerve, carrying the visual information onward to the brain. Photoreceptors (rods and cones) detect light but do not send a direct nerve bundle out of the eye; they pass signals to bipolar and other interneurons. Horizontal and amacrine cells are interneurons that refine and integrate the retinal signal locally, but they do not contribute axons to the optic nerve. So, the optic nerve is made up of the axons of retinal ganglion cells.

The part of the retina that carries signals out to the brain is the retinal ganglion cells. Their axons bundle together at the optic disc and form the optic nerve, carrying the visual information onward to the brain. Photoreceptors (rods and cones) detect light but do not send a direct nerve bundle out of the eye; they pass signals to bipolar and other interneurons. Horizontal and amacrine cells are interneurons that refine and integrate the retinal signal locally, but they do not contribute axons to the optic nerve. So, the optic nerve is made up of the axons of retinal ganglion cells.