bild

Embyro formation. Computer artwork of a ball of cells that resulted from a fertilized egg cell. A sperm cell fertilized the egg cell, forming a zygote which has genetic material from the mother and father. The cell divided several times to form this ball of cells in the first stage of embryonic development. If it successfully implants into the wall of the uterus, it can then develop into a new human baby during pregnancy. (KEYSTONE/SCIENCE PHOTO LIBRARY/Christian Darkin) === ===