Eye
Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptor cells in conscious vision connect light to movement. In higher organisms the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.
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Famous quotes containing the word eye:
“But man postpones or remembers; he does not live in the present, but with reverted eye laments to the past, or, heedless of the riches that surround him, stands on tiptoe to foresee the future. He cannot be happy and strong until he too lives with nature in the present, above time.”
—Ralph Waldo Emerson (1803–1882)
“The genius is a genius by the first look he casts on any object. Is his eye creative? Does he not rest in angles and colors, but beholds the design,—he will presently undervalue the actual object.”
—Ralph Waldo Emerson (1803–1882)
“Every age has a keyhole to which its eye is pasted.”
—Mary McCarthy (1912–1989)