What Are Stem Cells?
Stem cells differ from normal cells in several key ways. First of all, stem cells can divide themselves and have a relatively long shelf life as far as human cells are concerned. Stem cells are also cells that are not assigned a certain cell type or category, but which can become assigned and turn into a specialized cell type. A human skin cell, for example, is only capable of being a human skin cell and cannot change to become another type of cell. A human stem cell, on the other hand, can become a skin cell, a bone cell, or any other kind of human cell.
Where Are Stem Cells Found?
There are three basic types of stem cells. Fetal stem cells are found in human beings during the fetal stage of development and can be harvested from aborted fetuses or from the umbilical cord of a newly delivered baby. Embryonic stem cells are found in embryos and are generally harvested from frozen embryos that are designated to be incinerated as medical waste. Adult stem cells, on the other hand, are found in many different tissues within the human body and can be harvested, to a limited extent, without harming the individual or causing excessive pain.
What is the Debate Regarding Stem Cells?
Fetal stem cells and embryonic stem cells are both relatively controversial in society because of religious and political convictions. The fact that both types are harvested, or can be, from aborted fetuses or embryos has many convinced that the entire process is wrong. At the same time, however, the scientific community wishes to experiment with such stem cells on a widespread basis, because it is believed that they may help to cure many different diseases. Adult stem cells, on the other hand, have both sides of the issue excited because they can be harvested from adult human beings without harming the person. It remains to be seen, however, whether adult stem cells will perform as well as fetal stem cells and embryonic stem cells in research.