Subject: some questions about stem cells...

I'm not as knowlegeable about stem cells as some of the others submitting 
questions here so if possible I hope you can try not to be overly technical?

How many types of stem cells are there?

Why can't stem cells from any animal be used and just replace the DNA from a 
human cell.  Wouldn't that bypass the controversy about using human embrionic 
stem cells?

Why can't stem cells just keep dividing and be used to produce as many other 
stem cells as is needed instead of having to keep harvesting embrionic stem 
cells?

Could stem cells be used as a treatment for some neurological conditions such 
as schizophrenia or even autism as a means of repairing that affected part of 
the brain?


Is there a way to change any cell back into a stem cell?

Re: some questions about stem cells...