Embryonic Stem Cells
Definition of ESCs
Embryonic stem cells (ESCs) are capable of propagating themselves indefinitely and can retain their ability to make all cell types within the organism. They form at the blastocyst stage of development. A blastocyst is a hollow ball of cells that is smaller than a pinhead. It has three structures- trophoblast, blastocoels and inner cell mass (Mandal, 2001). The embryonic stem cells lie within this ball of cells. Firstly, they are derived from embryos, specially obtained from eggs that have been fertilized in vitro (Mandal, 2001). They are not fertilised within a woman’s body but in an in-vitro fertilization clinic or laboratory. They can live and grow in special solutions in test tubes or petri dishes in laboratories. Eventually, the excess embryos are frozen and later voluntarily donated for research purposes (Mayo, 2010).
The second way in which scientists can get embryos is via therapeutic cloning. This technique merges a cell from the patient who needs the stem cell therapy, with a donor egg. The nucleus is removed from the egg and replaces the nucleus of the patient 's cell (Rippon, H. J. & Bishop, A. E., 2004). This egg is stimulated to divide either chemically or with electricity. The resulting embryo carries the patient 's genetic material. This minimises the risk that one’s body will reject the stem cells when they are implanted (Watson, 2012).
Uses of ESCs
ESCs provided a simple model system to study the basic processes of early embryonic development and cellular differentiation. This improves our understanding about the development of fertilised egg and provides insight on how adult tissues are maintained and repaired (Cattaneo, 2012). Not only that, since they are derived from human blastocysts, they can also be used for cell-based therapies in which virtually any tissue or cell could be produced ‘to order’ in the laboratory (Rippon, H. J. & Bishop, A. E., 2004). Because of this versatility, embryonic stem cells have the highest
Embryonic stem cells (ESCs) are capable of propagating themselves indefinitely and can retain their ability to make all cell types within the organism. They form at the blastocyst stage of development. A blastocyst is a hollow ball of cells that is smaller than a pinhead. It has three structures- trophoblast, blastocoels and inner cell mass (Mandal, 2001). The embryonic stem cells lie within this ball of cells. Firstly, they are derived from embryos, specially obtained from eggs that have been fertilized in vitro (Mandal, 2001). They are not fertilised within a woman’s body but in an in-vitro fertilization clinic or laboratory. They can live and grow in special solutions in test tubes or petri dishes in laboratories. Eventually, the excess embryos are frozen and later voluntarily donated for research purposes (Mayo, 2010).
The second way in which scientists can get embryos is via therapeutic cloning. This technique merges a cell from the patient who needs the stem cell therapy, with a donor egg. The nucleus is removed from the egg and replaces the nucleus of the patient 's cell (Rippon, H. J. & Bishop, A. E., 2004). This egg is stimulated to divide either chemically or with electricity. The resulting embryo carries the patient 's genetic material. This minimises the risk that one’s body will reject the stem cells when they are implanted (Watson, 2012).
Uses of ESCs
ESCs provided a simple model system to study the basic processes of early embryonic development and cellular differentiation. This improves our understanding about the development of fertilised egg and provides insight on how adult tissues are maintained and repaired (Cattaneo, 2012). Not only that, since they are derived from human blastocysts, they can also be used for cell-based therapies in which virtually any tissue or cell could be produced ‘to order’ in the laboratory (Rippon, H. J. & Bishop, A. E., 2004). Because of this versatility, embryonic stem cells have the highest
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