Certified Ophthalmic Assistant Practice Exam

Which eye structure controls the amount of light entering the eye?

1. Cornea

2. Iris

3. Lens

4. Retina

The correct answer is: Iris

The correct answer is the Iris. The iris is the colored part of the eye that controls the size of the pupil, which in turn controls the amount of light entering the eye. By constricting or dilating the pupil, the iris adjusts the amount of light that reaches the retina at the back of the eye, helping to regulate the amount of light needed for optimal vision in different lighting conditions. The other options are not correct: - The cornea is the clear outermost layer of the eye that helps to focus light. - The lens helps to further focus light onto the retina. - The retina is the light-sensitive tissue at the back of the eye that sends visual signals to the brain.