What is a Stem Cell?Updated a month ago

A stem cell is a cell that can duplicate itself endlessly and to become cells of virtually any organ and tissue of the body. Embryonic stem cells are cells extracted from the blastula, the very early embryo. They have an exceptional ability to duplicate in vitro, that is, in a test tube, and to become cells of almost any tissue. Adult stem cells are cells found in an organism after birth. Until the early 2000s, it was believed that adult stem cells could only transform into blood cells, bone, and connective tissue. But research over the past 2 decades has revealed that adult stem cells have capabilities comparable to embryonic stem cells, being able to transform into cells of the tissue in which they migrate.