Essay about A Research On Stem Cells

1867 Words Apr 18th, 2016 null Page
STEM CELLS
A stem cell is that cell which is not specialised. It is the cell which subdivides and forms other cells. The split cell may remain as the stem cell or form other specialised cells like the red blood cells, white blood cells, a muscle cell or brain cell. These cells serve as the repair mechanism in the animal or plant. It is capable of subdividing as long as the animal or plant is alive.
Stem cells have two key distinguishing features from other cells; they are not specialized but rather they do renew themselves through cell division. These cells are capable of staying inactive for long periods without dying. Secondly, these cells can be made organ-specific under some special conditions . Stem cells in some organs like pancreas and heart only divide under special conditions.
There are two types of stem cells:
Embryonic stem cells; these are stem cells from a four or five-day human embryo. A sperm cell and a female ovum cell fuse to form a zygote which is a single cell. The zygote then subdivides to form more cells. After four to five days, before implantation unto the walls of the uterus, a blastocyst is formed. This blastocyst consists of the embryoblast which is the inner cells and the outer cells called trophoblast which forms part of the placenta. The embryoblast is differentiated to form all the other body parts of the human body.
Adult stem cells; they are also called somatic stem cells. These are the type of stem cells which exist after the embryonic…

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