colour blindness
a general term for a number of conditions in which there is a failure to distinguish certain colours. It is more prevalent in males than in females and is usually inherited. The most common form is Daltonism, in which reds and greens are confused. This is a SEX-LINKED DISORDER , the recessive gene responsible being carried on the X - chromosome and hence more likely to be present in males. The cause of colour blindness is thought to be a failure in the operation of the CONES , which detect colours.
Most of us see our world in color. We enjoy looking at a lush green lawn or a red rose in full bloom. If you have a color vision defect, you may see these colors differently than most people.
There are three main kinds of color vision defects. Red-green color vision defects are the most common. This type occurs in men more than in women. The other major types are blue-yellow color vision defects and a complete absence of color vision.
Most of the time, color blindness is genetic. There is no treatment, but most people adjust and the condition doesn't limit their activities.
colour-blindness