Final answer:
The pupil is the part of the eye that allows light to enter the posterior chamber, which is then focused onto the retina. It is controlled by the iris, which adjusts the pupil size in response to light intensity.
Step-by-step explanation
The human eye is a sophisticated organ with layers responsible for various functions. The outermost layer, called the fibrous tunic, comprises the cornea and sclera. The cornea performs a crucial role by being transparent and allowing light to enter the eye.
Then, the light passes through the pupil, which is the opening within the iris—the colored part of the eye. The iris controls the size of the pupil, dilating or constricting it depending on the brightness of the light to regulate how much light enters the posterior cavity of the eye.
This cavity contains the retina, which is essential for vision as it converts light into neural signals that are processed by the brain. The eye also includes two chambers filled with different fluids: the anterior cavity, containing aqueous humor, and the posterior cavity, containing vitreous humor.
The portion of the eye that allows light to pass into the posterior chamber is the pupil. The pupil is a hole at the center of the eye, controlled by the colored part of the eye called the iris. The iris constricts in bright light and dilates in dim light, regulating the amount of light entering the eye.