Stem cells are mysterious. They are cells that make or replenish other cells. For example, when you donate blood, your stem cells are in charge of replenishing your blood cells. Scientists have found stem cells throughout the body, each doing an assigned job. Some replenish blood cells, some replenish skin cells, and others repair heart tissue. These cells do not usually change jobs; they become specialists at making their particular cell types.
View the original article here: The Mysterious Embryonic Stem Cell – Discovery Institute