Multipotent. A Totipotent
stem cell can develop into
or generate a new
organism or part. A Pluripotent stem cell can become any type of cells in the body,
but they cannot grow into an entire organism. A multipotent stem cell can only
become some types of cells.
The first type of stem cells that was found was from
human embryos, they seem to be the best way to treat the
Parkinson’s disease, he Alzheimer’s disease, the juvenile
diabetes, and etc, because they are totipotent stem cells. When the human embryos are
3-5 days old from the day that they were fertilized, the stem cells are extracted. They
are then are placed in a dish, so they could be harvested to become any type of cells or
tissues, in the laboratory.
Other than being a large medical potential, they are also thought as being killing
human lives because when the stem cells are extracted, it ends the life of the embryo.
Some people think that killing the embryo is also a kind of murder. But, some say that
is not morally wrong because they can save other people’s lives and decrease human
suffering.
Later, researchers found out another way to obtain stem cells. Stem cells can be
also found in adults, not only the embryo, stem cells found in the bone marrow can
also develop into other types of cells in the human body. They can be used to cure the
Parkinson’s disease and can be used to treat other diseases without ending the lives of
the embryos.
In certain conditions, some kinds of adult stem cells seem to be able to
differentiate into many different types of cells. These stem cells may be able to treat
many serious disease if the differentiation can be controlled in the laboratory. By a
process of transdifferentiation or plasticity, adult stem cells may be able to form other
specialized types of tissues.
There are two types of stem cells in the bone marrow. There is the Hematopoietic
stem cell and the Bone Marrow Stromal cells. The Hematopoietic stem cell forms all
types of blood cells in the body and the Bone Marrow Stromal cell generates
cartilage, fat, bone, and fibrous connective tissue.
Parkinson’s disease causes the death of brain cells to produce dopamine, it
produces effects such as increased blood pressure and heart rate. Researchers
discovered that the umbilical cord blood stem cells might help speed up the recovery
of the Parkinson’s disease. It might also be able to cure the Alzheimer’s disease and
avoid using embryonic stem cells.
In conclusion, stem cell research helps decrease human suffering and finds ways
to cure serious diseases. Researchers are finding other ways and uses of stem cells, so
they do not involve in using embryonic stem cells, which is said to be killing a
human’s life.
Bibliography
Websites:
http://www.hosppract.com/genetics/9912mmc.htm
http://www.laskerfoundation.org/news/weis/tcloning.html
http://home.earthlink.net/~zaptos/website/overview/overview.html
http://www.stemcells.nih.gov/index.asp
Books:
Molecular Biology of the Cell: Third Edition, Alberta- Watson, Garland Publishing, Inc., New York, 1994