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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.


pronucleus British  
/ ˌprəʊˈnjuːklɪəs /

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of pronucleus

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The DNA from mum and dad form two balls of genetic information in the embryo called pronuclei, which will fuse to create the genetic blueprint for a child.

From BBC

Next, the researcher empties a fertilized donor egg of its genetic material and squirts the pronuclei into the hollow egg.

From Nature

The egg nucleus, now known as the female pronucleus, and each body contain the reduced or haploid number of chromosomes.

From Project Gutenberg

Researchers would take a fertilized egg and remove the two pronuclei, the sperm and egg's DNA before they combine, while leaving behind any mitochondria.

From Science Magazine

In Echinus, for instance, the two pronuclei fuse, and the spindle and chromosomes are formed from the zygote nucleus, whereas in the mouse the two pronuclei retain their distinctness during the formation of the chromosomes.

From Project Gutenberg