Which part of the eye is responsible for focusing light on the retina?

The part of the eye that is responsible for focusing light on the retina is the lens. Here are the steps of how it works:

1. Light enters the eye through the cornea, the clear, dome-shaped surface that covers the front of the eye. The cornea bends - or refracts - this incoming light.

2. The light then passes through the pupil, the circular opening in the center of the colored part of the eye (the iris). The iris adjusts the size of the pupil and controls the amount of light that can enter the eye.

3. The light then hits the eye's lens. The lens sits behind the iris and is clear and colorless. The lens' job is to focus light rays onto the retina, the light-sensitive tissue at the back of the eye.

4. The lens changes its shape to bend the light rays more or less, as needed, to focus light onto the retina. This process is called accommodation.

5. The focused light rays are then converted into images by the cells in the retina and sent through the optic nerve to the brain, where they are interpreted as the images we see.