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How is the female pronucleus formed during fertilization?
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Fertilization
Fertilization occurs when a sperm cell penetrates and fuses with an egg (ovum).
During fertilization, the formation of the female pronucleus is a critical step in the maturation of the egg.
When a sperm successfully penetrates the egg, the oocyte initiates its final maturation division. During this process, the oocyte separates the second polar body, which reduces its chromosomal content to a single set of 23 chromosomes. Following this division, the oocyte nucleus reconstitutes itself and is referred to as the female pronucleus.1
Once formed, the female pronucleus is prepared to unite with the male pronucleus—which is derived from the head of the fertilizing sperm—within the egg cytoplasm to form the zygote.12