Which layer of the eye contains millions of photoreceptors?

The retina is the layer of the eye that contains millions of photoreceptors, which are specialized cells responsible for capturing light and converting it into electrical signals that are sent to the brain for visual processing. This layer is crucial for vision, as it includes two main types of photoreceptors: rods, which are sensitive to low light levels and help with night vision, and cones, which are responsible for color vision and function best in bright light conditions.

The other structures in the eye have different roles: the cornea is the transparent front layer that refracts light, the iris is the colored part of the eye that controls the size of the pupil and therefore the amount of light entering the eye, and the lens focuses light onto the retina. While all of these components contribute to the overall function of vision, it is the retina that specifically contains the necessary photoreceptors for capturing visual information.