Which ocular structure absorbs most of the UV-A and UV-B light transmitted to the eye?

The lens is the ocular structure that absorbs the majority of UV-A and UV-B light transmitted to the eye. This is an important function because excessive UV exposure can lead to cellular damage and potential pathologies, such as cataracts or other types of lens opacities.

In particular, the lens has a unique composition of proteins and a high concentration of antioxidant molecules, which contribute to its ability to filter out harmful ultraviolet light while allowing visible light to pass through. The lens does this efficiently, absorbing the most harmful wavelengths of UV light before it can reach the retina, thereby protecting the inner structures of the eye.

While the cornea does absorb some UV light, it primarily protects against UV-B radiation rather than both UV-A and UV-B. The ciliary body and the iris are involved in other functions, such as accommodation and the regulation of pupil size, respectively, but they do not play the same significant role in UV light absorption as the lens. Thus, the lens's effective filtering properties make it the primary structure responsible for protecting the eye from UV radiation.