there's a few ways to go about it.
One type of stem cell can be found beneath your teeth, possibly only in childhood though, i forget. And those types of stem cells are not reliable.
The other types can come from the clump of cells in a zygote. this is the ball of cells that forms after an egg has been fertilized and has started to divide a bunch of times. The important thing to note here is these cells DO NOT HAVE A FUNCTION YET. The reason stem cells are so important is because they can change into any type of cell that exists in the human body. ANY CELL, from a skin cell to a brain cell.. a liver cell a lung cell.. a cell in an artery.. a vein.. a bone cell.. etc etc. Bu they have not done this yet. They are still a generic cell. So its not like you're killing a fetus, you're growing a small ball of generic, unspecified cells. You're not growing a fetus to like 5 months then killing it and shreading it for cells.
Now to get these cells you dont have to fertilize an egg. There's a process now that is used that extracts a person's DNA. They then take an egg from a woman, and remove the genetic material from the egg. This egg on its own can NOT form into a child, an egg from a woman or a sperm from a man only has half the genetic material needed to create a child. So they take the DNA from one of your cells and they put it into this now empty egg shell, and stimulate it to start to divide. When it starts to divide it becomes stems cells.. a ball of stem cells in the form of a zygote.
You CAN harvest stem cells from a fertilized egg (introduce sperm to egg and watch it grow) But that would not be of as much use as a stem cell created from your own DNA because it would not be anywhere near as compatible, especially if the sperm or egg used is not yours.
So basically what they do is, take your own genetic material. Moveit from the inside of your own cell, into an empty egg shell, then this egg will start to divide and multiply. The eggs are usually grown for a couple days to get only as many cells are needed for research.
The MAIN problem i have with the people who oppose stem cell research is that they really don't know much or anything about it. They will openly admit that they have no clue on the subject yet they still object to it. Its like a deaf person telling someone they can't sing. It annoys me to no end.
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We Must Dissent.
Last edited by ObieX; 05-25-2005 at 04:04 AM..
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