Which area is not involved in light absorption and processing in humans?

The optic nerve is primarily responsible for transmitting visual information from the retina to the brain, rather than being involved in the absorption and processing of light. The optic nerve carries the signals generated by photoreceptor cells in the retina but does not participate in the initial processes of capturing light or performing visual processing itself.

In contrast, the retina contains photoreceptor cells (rods and cones) that absorb light and convert it into electrical signals. The cornea assists in focusing light onto the retina and plays a crucial role in optical refraction. The iris regulates the amount of light that enters the eye by controlling the size of the pupil, thus directly influencing how much light reaches the retina for absorption.

Therefore, the optic nerve's role as a conduit for visual information differentiates it from the other structures, which are integral to the light absorption and processing functions within the eye.