Soma - Greek for "body".
Senescence - changes in molecular and cellular structure resulting in the prevention of further cell division.
Symmetric division - an adult stem cell gives rise to two identical daughter cells.
Asymmetric division - an adult stem cell gives rise to one identical daughter cell and one progenitor cell that will terminally differentiate into a mature lineage.
"Stem cell niche" - the microenvironment wherein a stem cell resides which provides the necessary growth and differentiation signaling events which are conducive to both cellular division and differentiation.
Select key terms are defined below. For a complete list of glossary terms please refer to the book.