<P> A pronucleus ( plural : pronuclei ) is the nucleus of a sperm or an egg cell during the process of fertilization , after the sperm enters the ovum , but before the genetic material of the sperm and egg fuse . Sperm and egg cells are haploid , meaning they carry half the number of chromosomes of somatic cells . The male and female pronuclei do n't fuse , although their genetic material does . Instead , their membranes dissolve , leaving no barriers between the male and female chromosomes . Their chromosomes can then combine and become part of a single diploid nucleus in the resulting embryo , containing a full set of chromosomes . </P>
<P> A pronucleus ( plural : pronuclei ) is the nucleus of a sperm or an egg cell during the process of fertilization , after the sperm enters the ovum , but before the genetic material of the sperm and egg fuse . Sperm and egg cells are haploid , meaning they carry half the number of chromosomes of somatic cells . The male and female pronuclei do n't fuse , although their genetic material does . Instead , their membranes dissolve , leaving no barriers between the male and female chromosomes . Their chromosomes can then combine and become part of a single diploid nucleus in the resulting embryo , containing a full set of chromosomes . </P>
the fusion of the male pronucleus and the female pronucleus results in development of
the fusion of the male pronucleus and the female pronucleus results in development of
single diploid nucleus in the resulting embryo
single diploid nucleus in the resulting embryo