Strep throat is a contagious disease caused by infection with streptococcal bacteria, which causes inflammation and swelling of the mucous membranes lining the back of the throat and the tonsils.trep throat is a contagious disease caused by infection with streptococcal bacteria, which causes inflammation and swelling of the mucous membranes lining the back of the throat and the tonsils.
Once an egg cell is fertilized by a sperm, it will divide and become an embryo. In the embryo, there are stem cells that are capable of becoming all of the various cell types of the human body. For research, scientists get embryos in two ways. Many couples conceive by the process of in vitro fertilization. In this process, a couple's sperm and eggs are fertilized in a culture dish.
When the fertilized egg attaches itself to the uterine wall and begins to produce hCG it is called implantation. This typically occurs between 6 and 8 days after ovulation. The egg is fertilized in the outer part of the fallopian tube, generally within 12 hours of ovulation.After it is fertilized, the egg travels down the fallopian tube. The fertilized egg grows as it travels. It doubles, the grows to four cells and then to eight cells as it enters the uterus.Implantation occurs in the upper third of the uterus.Implantation sometimes can cause bleeding or minor spotting.fter it is fertilized, the egg travels down the fallopian tube. The fertilized egg grows as it travels. It doubles, the grows to four cells and then to eight cells as it enters the uterus. Implantation occurs in the upper third of the uterus. Implantation sometimes can cause bleeding or minor spotting.