3. STEM CELLS

• What are stem cells?


  Cells that differenciate to become specialised cells
• Undifferenciated cells are ...

  stem cells
• Stem cells can divide by mitosis to ...

  become new cells on the instruction they're given which then differenciate
• Where are stem cells found in?


  Early human embryos
• Early human embryos have the potential to...

  to divide and produce any kind of cell at all
• Where do all different types of cell found in a human come from in their development?

  Early embryos
• What are stem cells important for>


  Growth and development of organisms
• Adults have stem cells, but only found in ...

  certain places, like bone marrow
• In adults, what are stem cells used for?

  To replace damaged cells, to make new skin or blood cells
• What are the 3 problems with using stem cells?

  Rejection, tumour development, and disease transmission
• What are the problems with rejection of the stem cells?


  Patient's body may recognise the cells as a foreign object and trigger an immune response to try get rid of them.
• What can a patient do with the rejection of stem cells?


  Take drugs to suppress this response, but this makes them more susceptible to disease.
• What are the problems with tumour development?


  If scientists are unable to control the rate of the cell division in the patient, a tumour may develop.
• What are the problems with disease transmission?

  Viruses live inside cells and if donor stem cells are infected, it could be passed on and the recipient could get sicker.