DNA and Stem cell research
A stem cell is a "generic" cell that can produce exact replicas of itself indefinitely. A stem cell also has the ability to construct specialized cells for various tissues in the body -- such as heart muscle, brain tissue, and liver tissue. Scientists are able to maintain stem cells forever, developing them into specialized cells as needed. When researchers decide to use these stem cells they can choose from two different types. There is the embryonic stem cell and the adult stem cell. Embryotic stem cells are obtained either from aborted fetuses or fertilized eggs that are left over from in vitro fertilization. They are useful for medical and research purposes because they can produce cells for almost every tissue in the body. The adult stem cell is misleading in the fact that both children and adults have them. These type of stem cells are not as versatile because they can only be used for wherever they are taken from, such as blood, intestine, skin and muscle. Stem cell research will enable scientists to take undifferentiated stem cells and direct them into becoming a specific type of cell, which could then be used for hundreds or thousands of medical procedures. However, stem cell research brings up many ethical questions and concerns. Stem cell research is opposed by many pro-lifers; this is mainly Roman Catholics and conservative Protestants.