Embryonic Stem Cells. What is a stem cell?. Stem cells are unspecialized cells that have two defining properties: the ability to differentiate into other cells (form into any cell) the ability to self-regenerate (is the ability of stem cells to divide and produce more stem cells).
Stem cells are unspecialized cells that have two defining properties:
Embryonic stem cells are retrieved from early-stage embryos —cells that forms when an egg is fertilized with a sperm. Extracting stem cells from embryos raises big ethical questions.
Controversy about using embryonic stem cells
The embryos being used in embryonic stem cell research come from eggs that were fertilized at IVF clinics but never used for a pregnancy because they were no longer wanted or needed. Stem cells can live and grow in solutions in test tubes or petri dishes in labs.
Apart from replacing parts , stem cell research has other advantages. For one thing, stable amounts of human cells would be a benefit to the pharmaceutical industry, which could test new drugs on real, live and fairly normal human cells. If the meds worked, they could be put through animal and eventually human tests. Stem cells could increase the accuracy of early drug discovery tests while reducing costs and the need to use animals.