Stem Cell & Stem Cell Technologuy

WHAT IS A STEM CELL?
Every cell in the human body can be traced back to a fertilized egg that came into cxistcncc from the union of an egg and a spcnn. The human body is made up of not just one, but over 200 different types of cells and all of these cell types comes from a pool of stem cells in the early embryo. Stem cells are unspecialized cells that develop into specialized cells, which in turn makc up the different types of tissues in thc human body. [)unng the pend of early development as well as later in life. various types of stem cells give rise to specialized or differentiated cells, such as the skin, blood, muscle and nerve cells, which carry out the specific functions of the body (Figs 1.1 and 1.2). In humans, stern cells have been identified in the inner cell mass of the early embryo, in some tissues of the fetus, the umbilical cord, the placenta and in several adult organs. In some of the adult organs, the stern cells give rise to more than one specialized cell type within that organ (e.g.: the neural stem cells give rise to three different cell type found in the brain neuron glial cells and astrocvtcs) (F1s 1.3 to 1.5).In humans. Stem Cell have been identified in the inner cell mass of the early embryo, in some tissues of the feus, the umbilical cord, the placenta and in scvcral aduk organs. In some of the adult organs, the stem cells give rise to more than one specialized cell type within that organ (e.g.: the neural stem cells give rise to three different cell types found in the brain ncurons. glial cells and astrocyics) (FIgs 1.3 to 1.5).