stem cells

[kiran]

I know very little about tem cells. I know that they are present in the early embryonic stage.
Is there any other areas in our body excpt in embryonic stage where stem cells are present in humans.
How is it possible for stem cells to get modified into definite tissues?
can we use stem cell to regenerate organs like heart and kidneys?
What would be if the stem cells wouldnt be present?

[mith]

1.Yup, they're adult stem cells.
2.Yep, that's what they're for.
3.See 2.
4.Well, the regenerative ability would be serverely impaired not to mention some other stuff.

[MrMistery]

A little more info
1. You got stem cells in your brain that create neurons and in your bones that create blood cells.
2. It is the process of differentiation. Through a very complex genetically driven mechanism a stem cell can become one of the aprox 150 types of cells in our body
3. As mithril said, see 2
4. If embryonic stem cells wouldn't be present... No humans...
If adult stem cells would not be present: no humans also cause the stem cells in your bone marrow create red blood cells continously... An erytrocyte dies in 30 days so you won't last very long... Also it creates leucocites... You would die of the common cold

[Chris4]

There is also an hypothesis that the cells at the centre of a tumour are stem cells. Not sure if this has been proven or just a theory but its one explanation for why cancer drugs are often successful but the cancer can eventually recur, often being fatal. Scary thought and if it proves to often be the case, new drugs or treatments may be needed.

[MrMistery]

I guess you can say that, since cancer cells divide continuosly, just like stem cells

[chemistry_freako]

hmm cancer cells proliferate due to expression of oncogenes? =\
hmms - does it apply for all the types of stem cells? (omnipotent, totipotent, pluripotent..) =D