Living Environment
Period 3 Due: January 2009
What are stem cells?
Each year thousands of people die from causes such as diseases that are preventable but there are a number of deaths. Stem cells are found in unspecialized multi-cellular organism cells which are organisms like cats, plants and humans. Multicellular organisms contain million and even trillions of cells. Stem cells have the ability to produce adult mature specialized body cells and at the same time they can replicate themselves through mitotic cell division. There are two types of mammalian stem cells which are embryonic stem cells and adult stem cells. Embryonic stem cells are found in blastocysts. Blastocysts are thin-walled hollow structures in early embryonic development that contains a cluster of cells as much as 200 to 250 cells. Adult stem cells are found in tissues like the umbilical cord and placenta or from blood, bone marrow, skin or other tissues. In adult organism stem cells work in the system as a repair system for the body replenishing specialized cells, but maintain the normal turnover of regenerative organs like bone marrow and blood, etc.
Why are they Important?
The study of stem cells is not only important to get a better understanding of the body and the way it functions but, but also for our understanding of medical diseases such as cancer that have their origins in abnormalities of cell division and cell differentiation. A stem cell can be said to be “one of the most initial cells which is yet to be differentiated into any particular type of cell and it remains so until it receives a signal to develop into a specialized cell”. Stem cells are important because they have the potential to generate replacements for different organs and body tissues of the boy such as the heart, pancreas and nervous system. Using stem cells can open up the possibility to repair or replace organs damaged from some of the most devastating diseases....