Word: retina
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Dates: during 1930-1939
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From the rods of fresh-water fishes, he extracted the vitamin-nature of the substance now called vitamin A-2. From chicken retina he obtained the first light-sensitive pigment to be found in these structures...
This new pigment operates in one type of cone on the retina of the chicken's eye. In this one type of cone it has been found that the color filters and photosensitive substance are present making it a miniature color camera...
Eyes have two small types of elements on the retina, rods and cones. The rods are used in half light or in darkness, while the cones are used in color vision. It has already been known that there is a visional purple partly composed of vitamin A, which is used in seeing with the rods; it is this that has led to the recent research into the connection between night blindness and vitamin...
...Fastest reader ever tested, an 8-year-old high-school boy who evidently had an unusually large macula (a yellow spot in the retina, most sensitive point of vision), in one test read 2,202 words a minute with excellent comprehension...
Leukoma is opacity of the eye's cornea, that transparent coating which shields the iris and the pupil and is supported by the aqueous humor. Immediately behind the iris lies the crystalline lens, which focuses light images upon the retina. Leukoma may occur when the cornea is struck by a blow, is spattered with hot fluids or metals, or is diseased by smallpox, tuberculosis, trachoma, gonorrhea, syphilis. Provided that a person with an opaque cornea 1) can distinguish between light and dark and 2) has completely recovered from any contagious disease, Dr. Filatov last week declared that he could...