Do You See What I See? Human Tetrachromacy

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The eye sees color through the use of color recepting rods located in the eye this information is then sent to the brain which processes what you saw and what it means. Humans are typically trichromats meaning that we have three types of color receptors rods in eye these are red, blue, and green cones. These combination of rods allow you to see all other colors or shades. Color blind individuals have only two types of color receptors. The segments of DNA that control the rods in human eyes are located on the 23 X chromosome, this is why color blindness usually affects males. So color blindness is a deficiency in the types of cones but tetrachromacy is an abundance. What this means is that tetrachromats have an additional type of cone in there eyes, this is the orange cone. Because this mutation is caused by information from both 23 X chromosomes it can only occur in females. This sex linked trait allow the individual to potentially see up to 100,000,000 different colors. This is 100 times as many colors as a trichromat.