Sophomore Dennis Chao
Here are some fun facts about science that I would like to share with you!
There are interesting functions inside and outside of our body. All through life, the body is continually replacing cells of various tissues and organs. For instance, the blood cell tissues are produced continually, to the point where we can donate blood regularly – we produce some 100 billion new blood cells every day!
All our organs are constantly being regenerated; cells die and must be replaced by new cells. Some, including skin, intestine and liver, much do so more often than others. There must be cells in the body that are not yet differentiated and specialized, and can take on the role of cell replacement in various differentiated tissues.
A stem cell is a cell with a capacity for prolonged or unlimited multiplication. It is able to divide many times over, generating cells identical to itself. In addition, on receiving some outside stimulus, stem cells will give rise to a more differentiated type of cell. Thus, a stem cell is a “blank” from which differentiated cells can be generated, and also maintain the stock of “blank” cells needed for future requirements.
Moreover, stem cells are responsible for replacing lots of cells in specific organs are called tissue-specific stem cells. They have the ability to produce only cells of a specific tissue, be it skin, blood, heart, or even brain. Those stem cells can remain dormant, without dividing, for long periods.until the need arises to replace cells of that tissue. Then, the stem cells multiply and differentiate to generate the specialized cells of that specific tissue.
For instance, when the body is cut, skin stem cells start to divide and produce the type of cells that make up skin: keratinocytes(cells with pigment, which give color to skin) cells of the epidermis and hair follicle cells. This is how a cut heals and regenerates the damaged tissue.
Naturally occurring stem cells can be divided into two large groups: adult and embryonic stem cells. Adult stem cells form a large group including stem cells derived from any of an individual’s tissues after birth. Stem cells from the blood of a newborn baby’s umbilical cord or placenta, for instance, form a part of the “adult” group.