Color blindness
From Simple English Wikipedia, the free encyclopedia
Color blindness is a kind of blindness where people can not see colors very well. It is inherited as a genetic condition. People who have color blindness are not able to tell the difference between certain colors. The gene for color blindness is carried in the X chromosome. Since males have an X-Y pairing and females have X-X, color blindness can occur much more easily in males and is almost always passed to them by their mothers.
The two most common kinds of color blindness are "green/red" and "blue/yellow." With each of these, people have trouble telling apart between the first/second color. While the genetic defect causing people to have trouble telling blue/yellow apart is the second most common defect it is also extremely rare as the defect of have no colour receptors and seeing only black and white is even more so.
Color blindness is caused by bad functioning of the retina. One of the cones (Color Sensitive Receptors) containing one pigment selective for each of the colors (red, green, and blue) are diminished or totally absent.
The cone is part of the eye that gathers information that has color, and a rod gathers information that is black and white.