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Meissner’s corpuscle

Noun, pl. Meissner’s corpuscles 1. A type of mechanoreceptor; a type of nerve ending in the skin that is responsible for sensitivity to light touch. In particular, they have highest sensitivity (lowest threshold) when sensing vibrations lower than 50 Hertz. They are rapidly adaptive receptors. (wikipedia.org) 2. Any of the small elliptical tactile end organs in hairless skin containing numerous transversely placed tactile cells and fine flattened nerve terminations. (merriam-webster.com) 3. A sensory nerve ending that is sensitive to mechanical stimuli, found in the dermis in various parts of the body. (Google Dictionary) Syn: Tactile corpuscles, corpuscle of Meissner Name origin: Named after Meissner, Georg (1829–1905), German anatomist and physiologist. Meissner conducted in 1851 intensive comparative microscopic investigations on the fibers and cells of the common trunk of the vestibular and cochlear nerves. In 1852 he studied the tactile corpuscles of the skin which now bear his name. He published other papers dealing with the problems of microscopy, particularly those relating to the skin. In 1857 he published a description of the nerve plexus in the submucosa of the intestinal wall....

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Melanism

/ˈmeləˌnizəm/ Noun 1. A development of dark-colored pigment in the skin or its appendages and is the opposite of albinism. Historically, it was also the medical term for black jaundice. (wikipedia.org) 2. Congenital excess of melanin pigmentation in the skin, hair, feathers and/or eyes; the condition of being melano. (wiktionary.org) 3. Unusual darkening of body tissues caused by excessive production of melanin, esp. as a form of color variation in animals. (Google Dictionary) 4. A condition characterized by abnormal deposits of melanin (especially in the skin). (wordnetweb.princeton.edu) 5. An increased amount of black or nearly black pigmentation (as of skin, feathers, or hair) of an individual or kind of organism. (merriam-webster.com) Word origin: From Greek melano-, comb. form of melas (genitive melanos) “black, dark,...

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Membrane

/ˈmemˌbrān/ Noun, pl. membranes 1. A mechanical, thin, flat flexible part that can deform or vibrate when excited by an external force. (wiktionary.org) 2. A flexible or semi-flexible covering or waterproofing whose primary function is to exclude water. (wiktionary.org) 3. A thin layer of tissue that covers a surface, lines a cavity, or divides a space or organ. (medical-dictionary.thefreedictionary.com) (Biology) 1. A thin layer of tissue covering a surface or lining a cavity, space or organ. (biology-online.org) 2. A flexible enclosing or separating tissue forming a plane or film and separating two environments (usually in a plant or animal). (wiktionary.org) 3. A cell membrane. (biology-online.org) (Chemistry) 1. A thin pliable sheet of material that is permeable to substances in solution. (wiktionary.org) Word origin: A term in anatomy, from Latin membrana “a skin, membrane; parchment (skin prepared for writing),” from membrum “limb, member of the...

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Memory

/ˈmem(ə)rē/ Noun, pl. memories 1. The area of cognitive psychology that studies memory processes. (wordnetweb.princeton.edu) 2. That faculty by which sensations, impressions, and ideas are stored and recalled. (medical-dictionary.thefreedictionary.com) 3. Complex mental function having four distinct phases: a. memorizing or learning b. retention, c. recall d. recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory. The area of cognitive psychology that studies memory processes; he taught a graduate course on learning and memory.The cognitive processes whereby past experience is remembered; he can do it from memory; he enjoyed remembering his father.The power of retaining and recalling past experience; he had a good memory when he was younger.The recollection of past events and experiences stored from learning and instinctive behaviour. (biology-online.org) 3. Persistent modification of behavior resulting from experience. (The American Heritage® Medical Dictionary) 4. The capacity of a material, such as plastic or metal, to return to a previous shape after deformation. (The American Heritage® Medical Dictionary) 5. The capability of the immune system to produce a specific secondary response to an antigen it has previously encountered. (The American Heritage® Medical Dictionary) 6. A general term for a device that stores data in binary code on electronic or magnetic media in computers. (Mosby’s Dental Dictionary, 2nd edition) Word origin: From Latin memoria “memory, remembrance, faculty of remembering,” noun of quality from memor “mindful,...

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