In human beings, the secondary oocyte is released from the mature Graafian follicle of an ovary (ovulation). The oocyte is received by the nearby Fallopian funnel and sent into the Fallopian tube by movements of fimbriae and their cilia. The secondary oocyte can be fertilized only within 24 hours after its release from the ovary. The secondary oocyte is surrounded by numerous sperms but only one sperm succeeds in fertilizing the oocyte. Since, the second meiotic division is in progress, so the sperm enters the secondary oocyte. Second meiotic division is completed by the entry of the sperm into the secondary oocyte (fallopian tube). After this secondary oocyte is called ovum (egg).