FREE Stem Cell Essay - Example Essays
2.2. Stem cells: Stem cells are defined as those which have ability to divide indefinitely by self renewal to generate mature cells of a tissue through differentiation (Spangrude et al.,1998). Stem cells do not occur in all the tissues and these must be identified and purified to study their properties. One of the examples of stem cells which are isolated from humans is haematopoietic stem cells and is responsible for generation of haematolymphoid systems (Morrison and Weissman, 1994). Stem cells possess potential merits which enable it to be used in various therapies. The two types of mammalian stem cells identified are embryonic stem cells and progenitor cells. The embryonic stem cells arise from adult tissues whereas the progenitor cells repairs the system and is responsible for maintaining turn over of regenerative organs like blood, skin and intestine (Tuch, 2008). Properties of the stem cells include self renewal, a tendency to replicate several times by numerous cycles and potency, a capacity to differentiate into totipotent or pluripotent cell types (Tuch, 2008). Stem cell research is used to treat many disorders like cancer, Parkinsonâ€™s disease, Spinal cord injuries, multiple sclerosis and many more (Stem cell therapy, 2005).
A stem cell is essentially the of the human body. The stem cells inside an embryo will eventually give rise to every cell, organ and tissue in the fetus's body. Unlike a regular cell, which can only replicate to create more of its own kind of cell, a stem cell is pluripotent. When it divides, it can make any one of the 220 different cells in the human body. Stem cells also have the capability to self-renew -- they can reproduce themselves many times over.