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.
1 Fetal stem cells-These cells are taken from the germline tissues that will make up the gonads of aborted fetuses. 2  Umbilical cord stem cells-Umbilical cord blood contains stem cells similar to those found in bone marrow. Umbilical cord stem cells-Umbilical cord blood contains stem cells similar to those found in bone marrow. 2  Placenta derived stem cells-Up to ten times as many stem cells can be harvested from a placenta as from cord blood. 3  Adult stem cells-Many adult tissues contain stem cells that can be isolated.