Definition Of A Stem Cell

The classical definition of stem cells requires two properties. The ability to go through numerous cell divisions while keeping the undifferentiated state and the capacity to differentiate into specialized cell types.

The practical definition of a stem cell is the ability to regenerate tissue over a lifetime.

A human embryonic stem cell is defined by the presence of several transcription factors and surface proteins.

The molecular definition of a stem cell includes more proteins and is still a topic of research.