Q. What are Embryonic Stem Cells?

A. Embryonic stem cells come from eggs that have been fertilized in vitro i.e. they have not been fertilized in a woman's body. The eggs that are donated have the informed consent of the woman. The human embryos that are a few days old (four to five) and is a microscopic ball of cells. It is these embryonic stem cells that are causing the most excitement because they can, in theory, turn into any one of the different types of cell in the body.