2006-10-04 16:19:32 · 7 answers · asked by Cade 3 in Science & Mathematics ➔ Medicine
Why the name Stem? I am not sure due the bran stem... Thinking in what the cientist named stem?
2006-10-04 16:56:24 · update #1
The definition for "stem" in the Merriam-Webster Online Dictionary says, (noun) "3 : a line of ancestry : STOCK; especially : a fundamental line from which others have arisen" and "intransitive verb : to occur or develop as a consequence : have or trace an origin
The entry for "stem cell" states, (noun) "an unspecialized cell that gives rise to differentiated cells
So, the differentiated (tissue) cells "stem" from stem cells.
2006-10-04 18:27:49 · answer #1 · answered by Ashana 2 · 1⤊ 1⤋
Think of stem as the start of things. Stem cells can produce any kind of cell (as per the definition). The stem of a plant is the start of everything that goes after it.
2006-10-05 08:25:44 · answer #2 · answered by scaryclairy 4 · 0⤊ 0⤋
Because differentiated (specialized) cells "stem" from them. Stem cells are cells that haven't yet differentiated into specific body cells that will perform a specific function.
2006-10-04 23:22:13 · answer #3 · answered by Anonymous · 1⤊ 0⤋
A stem cell is a type of cell that has the ability to either divide for indefinite periods in culture to create more stem cells, or to give rise to specialized cells. Because of their ability to develop into any cell type, they could potentially provide an unlimited source of adult cells, such as bone, muscle, liver, or blood cells.
Several types of stem cells exist, which will be described in the context of human development. To view a brief animation detailing the process of human development, click on “tutorial.”
After sperm fertilizes an egg, a zygote is formed which then has the potential to develop into a complete embryo. At this point, the fertilized egg is a totipotent stem cell, which means that it has the potential to create any type of cell necessary for embryonic development (this included extraembryonic membranes and tissues, the embryo itself, and all postembryonic tissues and organs).
In the first few hours after fertilization, the fertilized egg undergoes several cell divisions that produce identical totipotent cells. Because these cells are still totipotent, it means that any one of these cells has the potential to develop into an entire human being. In fact, identical twins are formed when two totipotent cells separate and develop into two genetically identical embryos.
The totipotent cells undergo several rounds of cell division. Approximately four days after fertilization, they begin to specialize and form a blastocyst. A blastocyst is a ball of cells consisting of a hollow outer layer of cells, within which is a cluster of cells call the inner cell mass.
The outer layer of cells will eventually form the placenta and other tissues that are needed for the support and development of the fetus. The inner cell mass will form all of the tissues of the human body, therefore, these are the cells that develop into the fetus. These inner cell mass cells are pluripotent. This means that they are able to give rise to many, but not all cell types necessary for fetal development (for example, they are able to give rise to fetal tissues, but not placental tissue). It is this pluripotent stem cell that is currently under investigation for medical use.
The pluripotent cells then further specialize into another type of stem cell, a multipotent stem cell. Multipotent stem cells are committed to give rise to cells that have a particular function, for example, blood stem cells give rise to red blood cells, white blood cells and platelets, and skin stem cells give rise to the different types of skin cells. Multipotent stem cells exist in both humans and adults, the best understood example being the blood stem cell. In every human being’s bone marrow, blood stem cells exist than constantly replenish the supply of red blood cells, white blood cells, and platelets.
2006-10-04 23:23:55 · answer #4 · answered by C.J. W 3 · 0⤊ 1⤋
Please see the webpages for more details on Stem cells and Stem cell research.
2006-10-05 10:47:01 · answer #5 · answered by gangadharan nair 7 · 0⤊ 0⤋
Because they can grow to anything from there,well, anything not too specialized...
2006-10-04 23:27:01 · answer #6 · answered by weebat 3 · 0⤊ 0⤋
brain stem...
2006-10-04 23:21:39 · answer #7 · answered by J G 4 · 0⤊ 2⤋