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 2 3. A three-day old, eight-celled embryo. Researchers at the Johns Hopkins University School of Medicine have devised a new technique, which helps couples that are affected by or are carriers of genetic diseases have in vitro fertilized babies free of both the disease in question and other chromosomal abnormalities.f the ten IVF embryos that they tested, they found that although only two were affected by GM1 gangliosidosis, an additional three were also aneuploid, leaving them with only five healthy embryos available for transfer into the uterus.