sikiämiseen

Sikiäminen, also known as conception or fertilization, is the biological process by which a new individual organism is produced. In humans and other sexually reproducing animals, it begins with the fusion of a male gamete, typically sperm, and a female gamete, an ovum or egg. This fusion results in the formation of a zygote, the first diploid cell of the new organism.

The process typically occurs within the female reproductive tract. Following sexual intercourse, sperm travel through the vagina, cervix, and uterus to reach the fallopian tubes. If ovulation has occurred, an egg will be present in the fallopian tube, and if sperm are present, fertilization can take place. One sperm penetrates the egg's outer layers, and its nucleus merges with the egg's nucleus, combining their genetic material.

Once fertilization occurs, the zygote begins a series of cell divisions, a process called cleavage, as it travels down the fallopian tube towards the uterus. Upon reaching the uterus, this developing embryo implants itself into the uterine wall, marking the beginning of pregnancy. Sikiäminen is a fundamental step in the continuation of species that reproduce sexually, involving the precise coordination of reproductive cells and their environment.