The light-sensitive layer at the back of the eyeball is the:

1. The retina lines the inner back surface of the eye. 2. It contains photoreceptors (rods and cones) that convert light into nerve signals. 3. The cornea is at the front, the iris controls the pupil aperture. _Source: syllabus Science, Ch 10 "The Human Eye and the Colourful World", §10.1_