Stem Cells in Medicine

• What do stem cells do?

  divide by mitosis to produce more cells which can differentiate into different types of specialised cells
• Embryonic Stem Cells meaning:

  Can differentiate into any type of specialised cell
• Where is the adult stem cell found and its role?

  Found in bone marrow and can differentiate into different types of blood cells
• Lots of conditions are due to ______ _____ meaning that they have been damaged in some way or dont work

  Faulty Cells
• Give me 3 examples of faulty cells.

  Type 1 Diabetes: damage to the pancreas cells that normally produce insulin.

  Paralysis: sometimes caused by damage to nerve cells

  Sickle cell anaemia: caused by misshapen red blood cells
• How do they replace faulty cells?

  1. Extract embryonic stem cells from an early embryo
  2. Grow them in a laboratory
  3. Stimulate them to differentiate into whichever type of specialised cells we want
  4. Give them to the patient to replace their faulty cells
• Name 2 Drawbacks

  1A Requires embryonic stem cells: Only one that are able to differentiate into any type of cell

  1B Only have a limited supply

  1C Some ethical Issues

  
  

  2A Rejection: the embryo and the patient have different genomes, so the patients immune system may reject the stem cells and tries to destroy them because it identifies them as foreign.

  2B Can reduce the risk by giving the patient medication to suppress their immune system their immune system (Doesnt always work)
• Name an alternative that can be used to replace faulty cells

  Adult stem cells, can be taken from the patient, it wont cause rejection, but can ONLY differentiate into different types of blood cells (can only help with sickle cell anaemia)
• Name 2 risks of using stem cells in medicine.

  Virus Transmission: if the donor stem cells are infected with a virus, when transferred into the patient, the virus is also transferred, also infect the patient

  Tumour Development: Since stem cells can divide so quickly, there is a chance they could get out of control once they've transplanted and it could develop into a tumour or cancer
• Which stem cell can only differentiate into types of blood cells?

  Adult stem cells
• Why are there ethical objects in using embryonic stem cells?

  1. human embryo have the potential for human life
  2. other people think that the benefits of curing existing people who are suffering is more important than the rights of the embryo
  3. the embryo that are used are usually unwanted ones from fertility clinic
• Which country allows in using embryonic stem cells?

  UK, but are tightly controlled