In the third week of pregnancy already ripened egg is ready to conceive. That is its confluence with the male sex cell. As a result of their compounds formed set of chromosomes, which forms a new cell - zygote. Fertilization is divided into three periods - this convergence of sperm and egg, the interaction between them and the actual occurrence of the sperm into the egg. After combining the nuclei of male and female cells - a zygote becomes a gene set. Next, the egg moves into the uterus, where it is its binding. Within a few days the embryo has about 32 cells and its form reminds mulberries.
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