What are stem cells and what are they good for?

( A stem cell)
( A stem cell)
Most cells in our body are specific types of cells. This means that they are liver cells, muscle cells, bone cells or many other possibilities. But before these cells become what they become, they are a type of rudimentary cell that is not yet defined as a specific cell in our body. This type of cell is the stem cell, which is a undifferentiated cell, meaning that it has not yet gone through the process of differentiation. Differentiation is the process of turning that undefined and undifferentiated stem cell into a defined, differentiated cell in our body.
Stem cells can be found in the gastrointestinal tract or in the bone marrow, from which they mutate to specific body cells and repair or renew our body tissues. Because of their capacity to mutate into every type of body tissue, they have high medical value, because they can renew damaged tissue in a patient's body. Bone marrow, for example, has been transplanted for years to help patients with leukemia (blood cancer). Although stem cells in our body can transform into blood cells and save a patient from leukemia, it is yet unclear if and how a stem cell could mutate into every type of cell when in another person's body.



(A Zygote)The only type of stem cell that can do that is the stem cell that composes the zygote. The zygote is the result of the fertilization of an egg by a sperm. From that stage on, they zygote keeps dividing its cells until it forms all the tissues that form the human body. Therefore, scientists have tried to use the zygote in experiments to see how they can make it mutate into the specific cell they want.  This process is called stem cell research, and will be explained in detail further on.Check out this video on stem cells:http://www.youtube.com/watch?v=mUcE1Y_bOQE&feature=player_embedded