The pupil is the opening located in the center of the iris of the eye. It controls the amount of light that enters the eye so that you can see clearly. The pupil size is controlled by muscles of the ...

Women can be colorblind, but it’s much less common than in men. Red-green color blindness, the most common type, is inherited through the X chromosome. Since males have only one X, they need just one ...

The Amsler grid is a good test for people with Macular Degeneration. The Amsler grid tests the condition of the center of the retina or "macula" ...