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color blindness
(Encyclopedia)color blindness, visual defect resulting in the inability to distinguish colors. About 8% of men and 0.5% of women experience some difficulty in color perception. Color blindness is usually an inherit...blindness
(Encyclopedia)blindness, partial or complete loss of sight. Blindness may be caused by injury, by lesions of the brain or optic nerve, by disease of the cornea or retina, by pathological changes originating in syst...Meryon, Charles
(Encyclopedia)Meryon, Charles shärl mĕryôNˈ [key], 1821–68, French etcher. His short life was saddened by poverty and neglect and complicated by recurring forms of mental aberration. Prevented by color blindn...vision
(Encyclopedia) CE5 Optic nerve vision, physiological sense of sight by which the form, color, size, movements, and distance of objects are perceived. Defects of vision include astigmatism, color blindness, far...Maxwell, James Clerk
(Encyclopedia)Maxwell, James Clerk klärk [key], 1831–79, great Scottish physicist. After a brilliant career at Edinburgh and Cambridge, where he won early recognition with mathematical papers, he was a professor...color
(Encyclopedia)color, effect produced on the eye and its associated nerves by light waves of different wavelength or frequency. Light transmitted from an object to the eye stimulates the different color cones of the...Dalton, John
(Encyclopedia)Dalton, John dôlˈtən [key], 1766–1844, English scientist. He revived the atomic theory (see atom), which he formulated in the first volume of his New System of Chemical Philosophy (2 vol., 1808...river blindness
(Encyclopedia)river blindness or onchocerciasis, disease caused by the parasitic nematode worm Onchocerca volvulus. The worm larvae are transmitted by the bites of blackflies (genus Simulium) that live in fast movi...glaucoma
(Encyclopedia)glaucoma glôkōˈmə [key], ocular disorder characterized by pressure within the eyeball caused by an excessive amount of aqueous humor (the fluid substance filling the eyeball). This causes pressure...night blindness
(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...Browse by Subject
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