colour blindness summary

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Below is the article summary. For the full article, see colour blindness.

colour blindness, Inability to distinguish one or more colours. The human retina contains three types of cone cells that absorb light in different parts of the spectrum. Absence of these types causes colour blindness to red, green, and blue. Colour blindness is a sex-linked recessive trait (see recessiveness) 20 times more common in men than in women.

John Dalton Summary

John Dalton was an English meteorologist and chemist, a pioneer in the development of modern atomic theory. Dalton was born into a Quaker family of tradesmen; his grandfather Jonathan Dalton was a shoemaker, and his father, Joseph, was a weaver. Joseph married Deborah Greenup in 1755, herself from