What are Stem Cells?
Stem cells are special cells in multicellular organisms which are capable of differentiating into a wide range of cells as needed. In other words, the cells themselves are not specialized like blood cells, nerve cells, and so forth, but they can make specialized cells to form an embryo or repair damage to an adult organism. This property has suggested that stem cells could be extremely useful in medical treatment, and many nations have established stem cell funding to explore the possibility of research and development with stem cells.
All multicellular organisms actually start out as a cluster of stem cells. As the stem cells divide and multiply, they differentiate themselves to make organs, muscle, bone, and so forth until a complete embryo is formed. Adults also have stem cells, although their precise origin is not fully understood. These adult stem cells trigger in response to serious injury to replace damaged tissues.
There are three types of stem cells. Embryonic stem cells are stem cells taken from an embryo. Cord blood stem cells come from the umbilical cord, which is rich in stem cells because it is of fetal origin. Adult stem cells are also known as somatic stem cells, and they are found in a range of locations around the adult body. The exact science and distribution of adult stem cells is still a topic of intense research.
In order to be considered a stem cell, a cell must possess two properties. The first is that the cell must not be specialized for a specific action, but it should be capable of generating specialized cells. In addition, stem cells can replicate themselves numerous times with errors, a process known as proliferation. Stem cell research is focused on exploring this unique properties, and scientists hope to some day be able to exploit stem cells, stimulating them to grow organs for people who need them, for example.
Research on stem cells is controversial in some parts of the world. Embryonic stem cells could only be harvested by taking an embryo until 2006, when scientists began to prove that stem cell lines could be created without sacrificing an embryo. Since some people are uncomfortable with the thought of killing an embryo, this issue raised a great deal of concern among many communities. Other critics are concerned that stem cell research may stray into the realm of cloning, and many communities oppose cloning of human beings, for a range of reasons. Most governments have focused on creating clear and understandable legislation about stem cell research, in the hopes of harnessing the immense potential of stem cells without causing controversy.
Written by S.E. Smith
