The adjustable ring of contractile and connective tissues that controls the amount of light entering the eye is the
A)lens.
B)cornea.
C)pupil.
D)iris.
E)retina.

Question

The adjustable ring of contractile and connective tissues that controls the amount of light entering the eye is the
A)lens. 
B)cornea. 
C)pupil. 
D)iris. 
E)retina.

Quizplus · Accepted Answer

The iris is the adjustable ring of tissue that controls the size of the pupil, which in turn controls the amount of light entering the eye. The lens is responsible for focusing the light that enters the eye and is not involved in controlling the amount of light. The cornea is the clear front surface of the eye that helps with focusing light and is not involved in controlling the size of the pupil. The retina is the layer of tissue at the back of the eye that contains the photoreceptor cells responsible for sensing light but is not involved in controlling the size of the pupil.

The Adjustable Ring of Contractile and Connective Tissues That Controls