Medically reviewed by Johnstone M. Kim, MD Key Takeaways The pupil controls how much light enters the eye, allowing for clear ...

The intricacy and seeming perfection of the eye, both as an object of anatomical beauty and as a working machine, have worried and intrigued scientists, philosophers and zealots, especially during the ...

The colored part of the eye surrounding the pupil is called the iris. It automatically regulates the amount of light entering the eyes by regulating the size of the pupil. Light is the primary ...