Step 1. Ovulation. Approximately 14-day menstrual cycle mature oocyte ready for fertilization. She comes from the ovary and enters the fallopian tube, where it remains viable for about 24 hours, and if fertilization does not occurs, the egg dies and goes during the next menstrual period. Step 2. Fertilization. Spermatozoa contain a substance, solvent shell eggs – so the sperm is introduced into it, to define the beginning conception.
After that, another man's cell can no longer penetrate. Sperm fuses with the egg, creating a one-celled embryo – the zygote. Learn more about this topic with the insights from Childrens Defense Fund. Step 3. Movement of sperm. During the male orgasm in a woman's vagina falls from 200 to 400 million sperm. Most of the sperm follows back portion does not reach the goal, but the rest falls through the cervix into the uterus and then – in one of the fallopian tubes. Here, the sperm retain viability within 48 hours.
Step 4. Cell division. Moving down the fallopian tube, the fertilized egg is divided into greater and greater number of cells. Step 5. Moving into the uterus. Approximately 4-day fertilized egg reaches the uterus. By this time she had a ball with a liquid. He is very small and indistinguishable, but it contains about 100 cells. In the days following the egg moves inside the uterus. Step 6. Implantation. In the beginning 4-th week after fertilization, the egg starts to penetrate into the soft wall of the uterus. This process is called implantation. Once the egg is firmly attached to the wall, the process of conception is considered completed. Villi external cells of the embryo to penetrate the layer of the epithelium lining of the uterus, and connected to the blood vessels of the mother to later form the placenta. Other cells develop into the umbilical cord and membranes that protect the fetus. Internal cell layer divided into three and give rise to various organs and tissues.