Stem Cells

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Stem cells
Nowadays, stem cells are the hottest topic in the medical field. More and more researches are performed to investigate these mystic cells. In order to go deeper into this topic and fully understand it, let’s first take a look at the stem cells themselves, their origins and characteristics which make them so unique and crucial for the medical field. Stem cells are very complex and complicated, and, that is why, it takes a lot amount of time to get to the bottom of their structure to be aware and understand how they work and which functions they possess. For the recent 50 years, the knowledge about these cells has developed a lot and still continues developing at the current time, too. They take their roots at the beginning of the 20th century when in 1908 Russian histologist, Alexander Maksimov, proposed the hypothesis about existence of the stem cells and coiled the name for them. Later on, in 1963, Canadian Scientists, James E. Till and Ernest A. McCulloch actually demonstrated the existence of self-renewing cells found in the bone marrow of mice. ( Silverstein, 12) It is impossible to say who exactly the founder of the stem cells was. When it comes to such kind of discussion, it is better to say that a lot of scientists put a great effort to contribute and give development of this field in medicine. All these contributions raised exploration in this area that have the most important and beneficial impact on the medicine. In the first five days the inner cells of the organism will create the entire body, including all of cell types and organs such as the heart, lung, skin, sperm, eggs and other tissues. This is where stem cells come into play to form and take on specialized functions in the body. Stem cells are defined as unspecialized cells that retain the ability to divide throughout life and take the place of specialized cells that get damaged, are lost, or that die. (Ralbovsky).The human body has over 200 different types of cells throughout it and a stem cell has the potential to replace just about all of them. They can initially duplicate or transform themselves into a different tissue type and function depending on what cells they are surrounded with such as nerve or skin cells. These cells are thought to divide indeterminately. Stem cells act as an "internal repair system" in tissue. They replace other cells as long as the person is alive. (Silverstein, 16) All stem cells have three main characteristics in common: they are unspecialized, they are capable of renewing and dividing into more for long periods, and they can give growth to specialized cell types. Stem cells also have the ability to repair many types of damaged tissue. Due to such wonderful properties, stem cells are used and very crucial for curing different types of diseases such as such as Parkinson’s, Alzheimer’s, and some types of cancer by replacing abnormal cells by stem cells which, in turn, will differentiate in any type of tissue.(Prentice) One of the interesting topics about stem cells which raises curiosity of scientists is the source of stem cells inside human body from which they may be removed with no harm for the human beings. Actually, there are two main types of stem cells. They are embryonic stem cells and adult stem cells. It was thought throughout the centuries that the only source of stem cells is embryonic cells, but, nowadays, there are others sources that can be used.Scientists have discovered some alternative means; such as certain unspecialized cells found in bone marrow, as well as umbilical cord blood and rare but unique skin cells. Let’s consider each of them. Embryonic stem cells are derived from an embryo. Most embryonic stem cells are taken from embryos that develop from eggs that have been fertilized in vitro fertilization then donated for research purposes with informed consent of the donors. (Ruse, 36) They are not derived from eggs fertilized in a woman's body. Most embryonic stem cells are derived from...
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