mesonephros

mesonephros /meso·neph·ros/ (-nef´ros) pl. mesoneph´roi   [Gr.] the excretory organ of the embryo, arising caudad to the pronephric rudiments or the pronephros and using its ducts.

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mes·o·neph·ros (mz-nfrs, -rs)

n. pl. mes·o·neph·roi (-nfroi)

The second of the three excretory organs that develop in a vertebrate embryo, replaced by the metanephros in higher vertebrates. Also called wolffian body.

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meso·nephric adj.

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mesonephros

[-nef′rəs] pl. mesonephra, mesonephroi

Etymology: Gk, mesos + nephros, kidney

the second type of excretory organ to develop in the vertebrate embryo. It consists of a series of twisting tubules that arise from the nephrogenic cord caudal to the pronephros and that at one end form the glomerulus and at the other connect with the excretory mesonephric duct. The organ is the permanent kidney in lower animals, but in humans and various other mammals it is functional only during early embryonic development and is later replaced by the metanephros, although the duct system is retained and incorporated into the male reproductive system. Also called mesonephron, middle kidney, wolffian body. See also metanephros, pronephros. mesonephric, mesonephroid, adj.

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mesonephros

(mez´nef´rs),
n the second type of excretory organ to develop in the vertebrate embryo. The organ is the permanent kidney in lower animals, but in humans and various other mammals it is functional only during early embryonic development.

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mesonephros

pl. mesonephroi [Gr.] the excretory organ of the embryo, arising caudal to the pronephros and using its duct. Displaced by the metanephros which becomes the kidney of the postnatal animal.