Dilation and constriction of the pupil are controlled by the
A) optic nerve.
B) lens.
C) retina.
D) iris.

Question

Quizplus · Accepted Answer

The dilation and constriction of the pupil are primarily controlled by the iris, which is the ring-shaped muscle that surrounds the pupil. This muscle can adjust the size of the pupil in response to changes in light intensity, emotional arousal, and other factors. The optic nerve helps to transmit signals from the retina to the brain, but it does not directly control the size of the pupil. The lens and retina are also important parts of the eye, but they are not directly involved in controlling pupil size.

Dilation and Constriction of the Pupil Are Controlled by the