>>23240819
Cool, here's your biology lesson:
"Human development begins after the union of male and female gametes or germ cells during a process known as fertilization (conception)."
[Moore, Keith L. Essentials of Human Embryology. Toronto: B.C. Decker Inc, 1988, p.2]
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"Although life is a continuous process, fertilization is a critical landmark because, under ordinary circumstances, a new, genetically distinct human organism is thereby formed. ... The combination of 23 chromosomes present in each pronucleus results in 46 chromosomes in the zygote. Thus the diploid number is restored and the embryonic genome is formed. The embryo now exists as a genetic unity."
[O'Rahilly, Ronan and MΓΌller, Fabiola. Human Embryology & Teratology. 2nd edition. New York: Wiley-Liss, 1996, pp. 8, 29.]
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"Zygote. This cell results from the union of an oocyte and a sperm during fertilization. A zygote is the beginning of a new human being (i.e., an embryo)."
[Moore, Keith L. and Persaud, T.V.N. The Developing Human: Clinically Oriented Embryology. 7th edition. Philadelphia: Saunders 2003, p. 2.]