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Glite Dictionary
pronucleus

pronucleus

1 9.9
The central part of a sperm or egg cell before they join to make one cell
  • noun
  • /ˌproʊˈnjuːkliəs/
  • Specialized
: pronúcleo
  • The egg cell completes its journey by merging with the male pronucleus contributed by the sperm.

And so there's an erasure program that's going on on day one that's removing the marks that marked these pronuclei as egg and sperm.

Examples

  • And so there's an erasure program that's going on on day one that's removing the marks that marked these pronuclei as egg and sperm.

    Stanford

  • During fertilization, the sperm forms a pronucleus that contains its genetic material.

  • It's called the maternal pronucleus carries the mother's chromosomes.

  • As the fertilization process begins, the female pronucleus is prepared to combine with the male pronucleus.

Surface Forms

pronucleus singular
pronuclei plural

Morphology

pronucleus = nucleus (semi-transparent) = pro + nucleus

The formation pro- + nucleus is morphologically regular, but 'pro-' meaning 'before' is a specialized scientific prefix that learners may not readily infer.

Etymology

Pronucleus is made of pro- meaning 'before' and nucleus meaning 'core' or 'center', the same root you see in nuclear. So a pronucleus is the nucleus of a sperm or an egg 'before' they join to form the zygote's nucleus.