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 muscles and connective tissue that controls the size of the pupil and thereby the amount of light entering the eye. The lens is the transparent, curved structure behind the iris that focuses the light onto the retina at the back of the eye. The cornea is the clear, dome-shaped outermost layer covering the iris, pupil, and lens. The retina is the sensory tissue at the back of the eye that contains photoreceptor cells that convert light into neural signals.

The Adjustable Ring of Contractile and Connective Tissues That Controls