What is a Stem Cell?
A lot of us hear about stem cell research, and we know that there is a controversy, but we don’t really even know what the controversy is over. So what is a stem cell?
Stem cell research started primarily with the findings of two Canadian Scientists in 1957. Stem cells are a certain type of cell common to all multi-cellular organisms, and by definition meet two criteria. First, they must possess the trait of self-renewal. They must be able to divide multiple times, while remaining in the same state after each division? And second, they must be able to turn into multiple other types of cells.
Well, Stem cells fall into two different categories. Embryonic Stem Cells and Adult Stem Cells.
Embryonic Stem Cells come from blastocysts. A blastocyst is an early stage embryo (about 4 to 5 days old in humans and consisting of 50-150 cells total). Embryonic Stem Cells have the ability to develop into more than 200 types of adult cells when given the proper stimulation for a specific cell type. Some favor research of an embryonic stem cell because of their long proven ability to become other types of cells.
Adult Stem Cells are stem cells that we would have after we are born. The name is a little misleading, but Adult Stem Cells are also found in children, and simply imply the maturity of the stem cell. In fact, one of the main ways that we obtain adult stem cells today is from the umbilical cord blood when a new baby is born. Previously, many believed that adult stem cells didn’t have the same ability to transform into other types of cells. But, recently that belief has been changed. Scientists believe that it possesses all of the abilities of Embryonic Stem Cells in terms of becoming other types of cells. Adult Stem cells also have a much longer track record of being used in treatments, and are therefore preferred by many.
So, now you know what a stem cell is. From now on when you hear about the debate, you’ll at least know what they’re talking about.
