Which part of the eye helps to protect it and assists in light refraction?

The cornea plays a crucial role in both protecting the eye and assisting with light refraction. As the outermost layer of the eye, it acts as a barrier against dust, germs, and physical damage, thus helping to shield the more delicate internal structures. Additionally, the cornea is transparent and has a curved shape, which is vital for bending (refracting) incoming light rays so they can be properly focused onto the retina at the back of the eye. This refraction is essential for clear vision.

In comparison, the iris primarily regulates the amount of light entering the eye by adjusting the size of the pupil, while the pupil itself is merely the opening through which light passes. The retina, on the other hand, is responsible for receiving light and converting it into neural signals, but it does not play a direct role in protecting the eye or refracting light. Therefore, the cornea is the key structure involved in both light protection and refraction.