Stem cells are found in embryos during the blastocyst stage of their development and in adult tissues.
Stem cells are undifferentiated cells. They have the potential to indefinitely replicate themself, producing more stem cells, or to differentiate into any other type of specialised cell. Stem cells play a crucial role in development, maintenance of tissues, and in repair following injury.
Stem cells found in different tissues of the developing and adult body are all slightly different. Embryonic stem cells are primarily for development and growth whereas those found in adult tissue are for reparation of damaged tissue.
Understanding the biological process underlying stem cell replication and differentiation is central to understanding the role they play in development and disease. Furthermore, it might allow for the harnessing of stem cells for therapeutic applications.
This image was made in response to research by Konrad Hochedlinger about understanding and manipulating cell fate.