Color blindness?

Question

What causes color blindness? What is effected when a person is colorblind?

Answer 1

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In the vast majority of cases, colour vision defects are of genetic origin, and are present at birth.
It is possible to acquire them through poisoning , adverse reaction to medication and certain other diseases.

The condition comes in several types and degrees of severity. Normally colour vision in the eye depends on the different stimulation of three types of light sensitive cells (cones). If one type of these is absent or abnormal, *some* colours but not all can be confused.
Most commonly red/yellow/green: "The tomato line", as a the changing tone of a ripening tomato corresponds to the poor discrimination very well.

Blue and yellow however are almost always safe colours and are not liable to be confused, even for people with very marked colour vision defects (Except for the rare "tritan" type, or the even rarer monochromats who have no colour discrimination at all)

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Answer 2

It's inherited, some people can't see red..

Answer 3

It is most often of genetic nature, but may also occur because of eye, nerve, or brain damage, or due to exposure to certain chemicals.

The different kinds of inherited color blindness result from partial or complete loss of function of one or more of the different cone systems. When one cone system is compromised, dichromacy results. The most frequent forms of human color blindness result from problems with either the middle or long wavelength sensitive cone systems, and involve difficulties in discriminating reds, yellows, and greens from one another.

Source(s):

http://en.wikipedia.org/wiki/Color_blind…

Answer 4

Cause...a recessive gene on the X chromosome (this is why men are colorblind more often then women.
Effect..depends on the type of colorblindness, ..they see colors but have a hard time distinguish between blue and green or other color combinations.

Answer 5

colour blindeness is a hereditary disease caused due to the absence of certain cones in the retina.it cant be cured.these persons are usually not given a driving license

Answer 6

Red-Green colourblindness is the most common form of colourblindness. People with it can't tell the difference between red and green.

It is an X-linked genetic disorder which means that men are more likely to have it. For a woman to have it she must have a father who is colourblind and a mother who is a carrier, for a amn to have it he must have a mother who is a carrier and his cahnce of getting it is 50%, if his mother is colourblind, he will be as well.

Answer 7

The cells coding the color are on a particular region of retina called the fovea.

On the fovea there are two types of cells the cones and the rods

The cones allow the vision of colours

We see all the colors and hues with 3 types of cones


I give you a link for test

One is sensitve to the red

One is sensitive to the green

One is sensitive to blue

The gene coding for the cones is on sexual chromosome X

If this chromosome has a recessive mutation , you loose oene type of cones. as the mutation is recessive, only men are affected, the women having two chromosomes X

The persons who lack the red cones are called protanopes
The persons who lack the green cones are called deuteranopes
The persons who lack the blue cones are called tritanopes (very rare)

Source(s):

http://www.toledo-bend.com/colorblind/Is…

Answer 8

Most color-blindness is caused by genetics, however, sometimes, people beocme color-blind because of brain, nerve, or eye damage. Color-blindness is very hard for one to imagine, as knowone can compare "normal vision" to "color-blind vision". Everyone is different when it comes to color-blindness, however, doctors and scientists have made ways to test and level how seriously color-blind a person is. For example, my dad and I are both color-blind. I've taken many tests for it, and doctors have concluded that I am very seriously color-blind. My dad can tell some colors apart that I can not, such as neon green and white, or red and green.


If you gave me a peice of white paper with neon green writing on it, I would not be able to read the writing, all I would see would be a white paper. The most common color-blindness is red/green color-blindness. Even people who have red/green color blindness might get other colors confused, however, as red/green color-blindness is not simply limited to those colors.

Some of the most common colors that color-blind people get confused with is neon green/white, red/green, red/brown, green/brown, purple/blue and yellow/green.

Source(s):

Being color-blind

Answer 9

Dear.................
Color blindness is not a form of blindness at all, but a deficiency in the way you see color. With this vision problem, you have difficulty distinguishing certain colors, such as red and green or blue and yellow. Red-green color deficiency is the most common form of color blindness; a less common form is blue-yellow color deficiency.

Color Blindness Symptoms and Signs
Do you have a hard time distinguishing if colors are red and green, or blue and yellow? This is the primary sign of this vision problem. Contrary to popular belief, it is rare that a color-blind person would see only in neutral colors or shades of gray.


Eye doctors often use Ishihara plates to determine the severity and type of color deficiency. Someone with normal color perception can see the numeral among the dots. But someone with red-green deficiency would have trouble discerning the red among the green.



What Causes Color Blindness?
Color blindness occurs when certain cells in the retina that normally respond to color do not respond as they should.

Usually, people with a color deficiency are born with it, and the problem affects more men than it does women. Color blindness is caused by a common X-linked recessive gene. This means that if you're color-blind, your mother must either be color-blind, or have normal vision but carry the color-deficient gene. Color-blind fathers pass the gene to their daughters only, who will have normal color vision unless their mother also carries the color-deficient gene.

Aging or disease can also damage retinal cells, and in extreme cases can lead to almost total color blindness.

Color Blindness Treatment
Color blindness cannot be cured. However, if you have difficulty distinguishing colors, or you've observed this difficulty in your child, see your eyecare practitioner.


Drivers who can't tell red from green can still recognize the order of colors on traffic lights. Photo: Serengeti.



Diagnosing color-vision deficiency early may prevent learning problems during the school years, since many learning materials rely heavily on color perception. If your child has a color deficiency, be sure to speak with his or her teachers about it, so they can plan their lessons accordingly.

Some people use special lenses for color blindness, which are filters available in either contact lens or eyeglass lens form. They are available from a limited number of eyecare practitioners in the United States and other countries.

You can also learn ways to work around your inability to pick out certain colors. For instance, you might organize and label your clothing to avoid color clashes. (Ask friends or family members to help!) And you might remember the order of things rather than their color (for example, the red light is at the top of a traffic light).

Causes of Colour Blindness
How can a person see, yet not see in color? What is color blindness and how does it work? Color blindness, or color vision deficiency, as it is also called, is the inability to distinguish colors and shades. This disorder varies in degrees from trouble distinguishing shades of the same color all the way to the inability to distinguish any colors at all. The latter is extremely rare, and is congenital. Only 8% of males and 1% of females display this type of color vision deficiency.


The most common cause of color blindness is a genetic defect. It is known that the defective gene is carried on the X chromosome, so males are almost exclusively the victim, and white males make up practically the entire percentage of victims. Females, however, are typically the carriers of the defective gene, so males get the defective gene from their mothers. So for the male who has color blindness, if he has a daughter, she will be a carrier of the defective gene, and her sons will have a 50% of being color blind, and her daughters will most likely be carriers. If he has a son, he will not have colorblindness. The color blind man's sisters have a 50% chance of being a carrier and her sons will have a 50% of being color blind. Most types of color blindness are hereditary, however there are some types that are not hereditary. With the aging process, there is aging of the lenses of the eye, which cause them to darken. Retinal and optic nerve diseases, and even some medications can cause this effect, as well.



There is no cure for color blindness. But, people can be taught to recognize colors by means such as brightness of colors or location. An example of the location would be a stoplight. The person would be taught that the red light is at the top, the yellow in the center and the green at the bottom. Another would be to learn that a stop sign is red, a yeild sign, and so forth. Sometimes, specially tinted eyeglasses can help. Check with your ophthalmologist if you suspect you are color vision deficient, to see which of these devices would be right for you.


Color blindness is essentially a defect. It is caused by a defect in the retina or the nerves of the eye. The first documentation of this disorder was made by a British Chemist named John Dalton, who did, in fact, suffer from this disorder. Total color blindness in which all color is seen as shades of gray, only, is called achromatopsia or monochromatism, is extremely rare. More common is partial color blindness. This type is technically termed dichromatism. It consists of the inability to differentiate between reds and greens and sometimes may involove blues and yellows. In the back of the eye, there are rods and cones. The cones pick up the color and the rods control the brightness, sort of like the knobs on your television. There are different cones for different colors. People with color vision deficiency have fewer of some cones than others, that is why there are different variations and degrees of color blindness. Some people may be more color blind than others. Being color blind does not effect your ability to get a driver's license. Most people with color blindness have good vision otherwise. However, some work such as policemen, medical personnel, firemen and transportation workers cannot be color blind for safety reasons and those applying for these jobs usually have to take a test for color blindness. Color blind people accomodate their deficiency in other ways, as afore mentioned, so one interesting tidbit is that they look for contour and outlines, not colors so they don't have problems with camoflauge. In World War II, color blind soldiers were used in spy planes to spot camoflauged German camps. If you have trouble distinguishing colors, check with your eye doctor for testing or find some neat

Answer 10

The most common causes are genetic damage/errors in the X chromosome.

This effects males more often than females due to the lack of a second X chromosome. The presence of an undamaged second X in females is usually enough to prevent the disorder.