0Stem cells are unspecialized(undifferentiated) cells that have the ability to differentiate into other cells, and self-regenerate. These cells divide to produce one daughter cell that remains a stem cell and one that divides and differentiates. Because the division of stem cells produces new stem cells as well as differentiated daughter cells, stem cells are self-renewing populations of cells that can serve as a source for the production of differentiated cells throughout life. Typically, stem cells generate an intermediate cell type or types before they achieve their fully differentiated state.
The intermediate cell is called a precursor or progenitor cell. The ability to differentiate is the potential to develop into other cell types. Depending on the ability to differentiate into other cell types, stem cells can be classified as totipotent, pluripotent and multipotent stem cells. The Totipotent stem cells can give rise to a fully functional organism as well as to every cell type of the body. Pluripotent stem cells can differentiate into all cell types mostly. The multipotent stem cell can differentiate into a limited number of closely related families of cells.
