What is the function of the retina in the eye?

The retina plays a crucial role in vision by detecting light with specialized receptor cells known as photoreceptors. These photoreceptors, which include rods and cones, are responsible for converting light into electrical signals. Rods are sensitive to low light levels and are essential for night vision, while cones are responsible for color vision and function best in bright light. When light hits these receptor cells, it initiates a biochemical process that generates signals, which are then transmitted to the brain through the optic nerve. This process is fundamental for our ability to see, as it allows the brain to interpret visual information based on the light patterns received.

In contrast to the other options, regulating pupil size is a function of the iris, focusing light involves the cornea and lens, and transmitting visual information is indeed a role of the optic nerve and brain, but it is not the primary function of the retina itself. The key aspect of the retina is its ability to detect light and initiate the visual process.