The function of the Iris is (c) Controlling the size of the pupil. The Iris, the colored, ring-shaped structure behind the cornea, regulates the amount of light entering the eye by adjusting the size of the pupil, the central opening in the middle of the Iris.
In bright light conditions, the Iris contracts, reducing the size of the pupil to limit the amount of light entering the eye and preventing overexposure. Conversely, in dim lighting, the Iris dilates, enlarging the pupil to allow more light to enter and improve visibility.
By adjusting the size of the pupil, the Iris helps to optimize visual acuity and clarity in varying light environments. This mechanism ensures that the appropriate amount of light reaches the retina for optimal vision while protecting the delicate structures of the eye from potential damage due to excessive light exposure. The Iris’s ability to dynamically regulate pupil size contributes to the eye’s adaptability to different lighting conditions.