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macula
macula
1. A patch of sensory hair cells in the utriculus and sacculus of the inner ear that provides information about the position of the body in relation to gravity. The hairs of the cells are embedded in an otolith, a gelatinous cap containing particles of calcium carbonate. Movement of the particles in response to gravity pulls the gelatinous mass downwards, which bends the hairs and triggers a nerve impulse to the brain (see illustration). 2. An area of the retina of the vertebrate eye with increased visual acuity. Maculae occur in some animals that lack foveae and often surround foveae in those animals that possess them. |
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"macula." A Dictionary of Biology. 2004. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "macula." A Dictionary of Biology. 2004. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O6-macula.html "macula." A Dictionary of Biology. 2004. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-macula.html |
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macula
macula (mak-yoo-lă) n. (pl. maculae) a small anatomical area that is distinguishable from the surrounding tissue. m. lutea the yellow spot on the retina at the back of the eye, which surrounds the greatest concentration of cones (see fovea).
—macular (mak-yoo-ler) adj. |
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"macula." A Dictionary of Nursing. 2008. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "macula." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O62-macula.html "macula." A Dictionary of Nursing. 2008. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-macula.html |
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macula
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MICHAEL ALLABY. "macula." A Dictionary of Zoology. 1999. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "macula." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O8-macula.html MICHAEL ALLABY. "macula." A Dictionary of Zoology. 1999. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-macula.html |
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macula
macula A dark spot on a planetary surface; pl.maculae. The name is not a geological term, but is used in the nomenclature of individual features, for example Tyre Macula on Europa.
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"macula." A Dictionary of Astronomy. 1997. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "macula." A Dictionary of Astronomy. 1997. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O80-macula.html "macula." A Dictionary of Astronomy. 1997. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-macula.html |
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