female pronucleus


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pronucleus

 [pro-noo´kle-us]
the haploid nucleus of a germ cell.
female pronucleus the haploid nucleus of the fully mature oocyte, which loses its nuclear envelope and liberates its chromosomes to meet the synapsis with those from the male pronucleus.
male pronucleus the nuclear material of the head of a spermatozoon, after it has penetrated the oocyte and acquired a pronuclear membrane.

female pronucleus

the nucleus of the ovum after fertilization but before the fusion of nuclear material from the sperm. The pronucleus is larger than the normal nucleus and has a diffuse appearance.
References in periodicals archive ?
For example, in sea urchins the sperm aster extends toward the female pronucleus and is thought to effect the migration of the two pronuclei (Zimmerman and Zimmerman, 1967; Longo and Anderson, 1968; Longo, 1976; Schatten, 1981; Bestor and Schatten, 1981; Sluder et al., 1985).
Activated eggs do not form blisters of cytoplasm when removed from cold treatment, although a small crescent of cytoplasm may form over the female pronucleus after 50 minutes.
In addition, the cytological studies revealed that the donor sperm incorporated into the egg cytoplasm, developed into the male pronucleus, and merged with the female pronucleus eventually in some interspecific crosses in molluscs, such as C.