Answer:
the retina of the eye contains photoreceptor cells that detect the light intensity, whether it is dim or bright, changing shape of iris.
Step-by-step explanation:
in dim light, the receptors detect the light intensity, and in order to allow us to see more clearly, the radial muscles in iris contract, making the pupil widen(dilate), so more light enters eye.
in case of bright light, he receptors detect the light intensity, and in order to allow us to see more clearly, the circular muscles in iris contract, making the pupil narrow(constrict), so less light enters eye