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.
Read more about Eye.
Famous quotes containing the word eye:
“Herein Fortune shows herself more kind
Than is her custom. It is still her use
To let the wretched man outlive his wealth,
To view with hollow eye and wrinkled brow
An age of poverty; from which lingering penance
Of such misery doth she cut me off.”
—William Shakespeare (1564–1616)
“Men of extraordinary success, in their honest moments, have always sung, “Not unto us, not unto us.” According to the faith of their times, they have built altars to Fortune, or to Destiny, or to St. Julian. Their success lay in their parallelism to the course of thought, which found in them an unobstructed channel; and the wonders of which they were the visible conductors seemed to their eye their deed.”
—Ralph Waldo Emerson (1803–1882)
“Loosed betwixt eye and lid, the swimming beams
Of memory, blind school of cuttlefish,
Rise to the air, plunge to the cold streams....”
—Allen Tate (1899–1979)