pronucleus

American  

[proh-noo-klee-uhs, -nyoo-] / proʊˈnu kli əs, -ˈnyu- /

noun

Cell Biology.

plural

pronuclei

1. either of the gametic nuclei that unite in fertilization to form the nucleus of the zygote.

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pronucleus British  

/ ˌprəʊˈnjuːklɪəs /

noun

1. the nucleus of a mature ovum or spermatozoan before fertilization

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Etymology

Origin of pronucleus

From New Latin, dating back to 1875–80; see origin at pro- ¹, nucleus

Example Sentences

The egg is then exposed to a chemical that causes the remaining pronucleus to replicate, thus giving the cell a full complement of genes.

From Time Magazine Archive

First, its own head rapidly increases in size, and takes on the appearance of a cell-nucleus: this is called the male pronucleus.

From Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions by Romanes, George John

Part of it is extruded, and part dissolved in the cell contents; only a very small part of it is left to form the basis of a fresh nucleus, the pronucleus femininus.

From The Evolution of Man — Volume 1 by Haeckel, Ernst Heinrich Philipp August

FIG.40.—Completion of the process of extrusion of the chromatic material; fn shows the two chromosomes retained in the egg forming the female pronucleus.

From The Story of the Living Machine A Review of the Conclusions of Modern Biology in Regard to the Mechanism Which Controls the Phenomena of Living Activity by Conn, H. W. (Herbert William)

Contraction of the skein, and formation of two U-or V-shaped chromatin fibres in each pronucleus.

From Darwin, and After Darwin (Vol. 1 and 3, of 3) An Exposition of the Darwinian Theory and a Discussion of Post-Darwinian Questions by Romanes, George John