pronephros

American  

[proh-nef-ros, -ruhs] / proʊˈnɛf rɒs, -rəs /

noun

Embryology.

plural

pronephroi, pronephra

1. one of the three embryonic excretory organs of vertebrates, which becomes the functional kidney of certain primitive fishes.

---

pronephros British  

/ prəʊˈnɛfrɒs /

noun

1. the first-formed anterior part of the embryonic kidney in vertebrates, which remains functional in the larvae of the lower vertebrates See also mesonephros metanephros

---

Other Word Forms

• pronephric adjective

Etymology

Origin of pronephros

1875–80; < New Latin < Greek pro- pro- ² + nephrós kidney

Example Sentences

The more complete replacements, such as the nephridia of the genital segment of Tubifex by a subsequently formed genital duct, may be compared with the succession of the nesonephros to the pronephros in vertebrates, and of the metanephros to the mesonephros in the higher vertebrates.

From Project Gutenberg

Figure 3, Sheet 17, is a generalized diagram of the uro-genital organs in the vertebrata; M.L. is the middle line of the body, G. is the genital organ, Pr. is the pronephros, or fore kidney, a structure which is never developed in the dog-fish, but which has functional importance in the tadpole and cod, and appears as a transitory rudiment in the chick.

From Project Gutenberg

The anterior part of the kidney, called the pronephros, disappears in the later larval stages.

From Project Gutenberg

With the exception of the reduction of the pronephros, what has been said of the development of the frog's nervous system, renal and reproductive organs, and skeleton, applies sufficiently to the fowl for our present purposes.

From Project Gutenberg

Tabulating these facts-- In the adult male: Pronephros disappears.

From Project Gutenberg