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pronucleus




The nucleus of a sperm or an (egg) prior to fertilization. Sperm and egg cells carry half the number of chromosomes of other nonreproductive cells. When the pronucleus of a sperm fuses with the pronucleus of an egg, their chromosomes combine and become part of a single nucleus in the resulting embryo, containing a full set of chromosomes.


Related categories

   • CELL BIOLOGY
   • GENETICS AND HEREDITY

Source: National Human Genome Research Institute