Difference between revisions of "AY Honors/Shells - Advanced/Answer Key"
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[[image:nacre.jpg|thumb|A piece of nacre]] | [[image:nacre.jpg|thumb|A piece of nacre]] | ||
| − | + | Rama SUCK MY DICK FUCKER | |
| − | Nacre is | + | '''Nacre''', also known as '''mother of pearl''', is an organic mixture of [[calcium carbonate]] (CaCO<sub>3</sub>) in the form of platy crystals of [[aragonite]] and [[conchiolin]] (a [[scleroprotein]]). |
| − | When a mollusk is invaded | + | Nacre is secreted by the [[ectoderm|ectodermic]] [[cell (biology)|cells]] of the [[Mantle (mollusc)|mantle tissue]] of certain species of [[mollusk]]. In these mollusks, nacre is continually deposited onto the inner surface of the animal's shell (the [[iridescent]] ''nacreous layer'', commonly known as ''mother of pearl''), both as a means to smooth the shell itself and as a defense against [[parasite|parasitic organisms]] and damaging detritus. |
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| + | When a mollusk is invaded by a [[parasite]] or is irritated by a foreign object that the animal cannot eject, a process known as ''[[encystation]]'' entombs the offending entity in successive, concentric layers of nacre. This process eventually forms what we call [[pearl]]s and continues for as long as the mollusk lives. | ||
==Research== | ==Research== | ||
Revision as of 08:14, 29 March 2005
Rama SUCK MY DICK FUCKER
Nacre, also known as mother of pearl, is an organic mixture of calcium carbonate (CaCO3) in the form of platy crystals of aragonite and conchiolin (a scleroprotein).
Nacre is secreted by the ectodermic cells of the mantle tissue of certain species of mollusk. In these mollusks, nacre is continually deposited onto the inner surface of the animal's shell (the iridescent nacreous layer, commonly known as mother of pearl), both as a means to smooth the shell itself and as a defense against parasitic organisms and damaging detritus.
When a mollusk is invaded by a parasite or is irritated by a foreign object that the animal cannot eject, a process known as encystation entombs the offending entity in successive, concentric layers of nacre. This process eventually forms what we call pearls and continues for as long as the mollusk lives.
Research
- Lin, A., and Meyers, M.A. 2005. Growth and structure in abalone shell, Materials Science and Engineering A 390(Jan. 15):27–41 (see abstract)
