mesonephros

[mez-uh-nef-ros, mes-, mee-zuh-, -suh-]
noun, plural mesonephroi [mez-uh-nef-roi, mes-, mee-zuh-, -suh-] . Embryology.
one of the three embryonic excretory organs of vertebrates, becoming the functional kidney of fishes and amphibians and becoming part of the tubules or ductules in the reproductive systems of higher vertebrates.


Origin:
1875–80; < Neo-Latin, equivalent to meso- meso- + Greek nephrós kidney

mesonephric, adjective
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World English Dictionary
mesonephros (ˌmɛsəʊˈnɛfrɒs)
 
n
pronephros See also metanephros the middle part of the embryonic kidney in vertebrates, becoming the adult kidney in fishes and amphibians and the epididymis in reptiles, birds, and mammals
 
[C19: New Latin, from meso- + Greek nephros kidney]
 
meso'nephric
 
adj

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American Heritage
Medical Dictionary

mesonephros mes·o·neph·ros (měz'ə-něf'rəs, -rŏs', měs'-)
n. pl. mes·o·neph·roi (-něf'roi')
The second of the three excretory organs that develop in a vertebrate embryo, replaced by the metanephros in higher vertebrates. Also called wolffian body.


mes'o·neph'ric adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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Encyclopedia Britannica
Encyclopedia

mesonephros

permanent kidney of amphibians and most fish, developing posterior to and replacing the pronephros of the embryonic and larval stages. It is a paired organ consisting of a set of nephrons having capsules that filter blood from the glomerulus and tubules whose cells reabsorb water and nutrients and secrete nitrogenous wastes. Glomeruli are absent in some marine fish; urine then forms solely in the tubules, a process that conserves water. The tubules empty into a long tube, the Wolffian duct, a remnant of the pronephros. In more advanced vertebrates the mesonephros develops in the embryo but is replaced after the 10th week in humans by the metanephros.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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Example sentences for mesonephros
The organ is located just in front of the kidney, or, mesonephros.
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