stem cells

• Stem cells

  Undifferentiated cells capable of becoming other types of cells, undergoing a process known as differentiation
• • Stem cells are UNDIFFERENTIATED cells that can differentiate into other cell types
• 1. Stem cells found in early HUMAN EMBRYOS, have the potential to turn into ANY cell type.

  
• 2. ADULT STEM CELLS exist too but are limited in the types of cells they can turn into. Are commonly found in BONE MARROW and can only differentiate into different types of BLOOD CELLS (eg. Red blood cells and White blood cells).

  
• STEM CELLS can be grown in labs and differentiated into specialised cells for MEDICINE or RESEARCH.
• • ADULT STEM CELLS can be used to treat diseases by replacing faulty BLOOD CELLS in patients.
• • EMBRYONIC STEM CELLS have potential in treating a variety of conditions, including DIABETES and SPINAL INJURIES.
• • THERAPEUTIC CLONING involves creating embryos with the same DNA as a patient, which can be used to produce stem cells with the same genetic information as the patient, to reduce risks of REJECTION.
• • In plants, stem cells are found in MERISTEM TISSUE, which are on the TIPS of plant shoots and roots where growth occurs.

  
• plant stem cells can differentiate into ANY type of plant cell.
• Plant stem cells can be used to produce identical CLONES of plants, this is useful for preserving RARE SPECIES of plant and producing CROPS with desirable traits like DISEASE and INSTECTICIDE RESISTANCE.

  
• stem cells can differentiate, therefore can form heart cells.

  
• 1. Adult can give consent
  2. cells will not be rejected

  
• • it can treat diseases.
  • cells of any type can be produced
  • would reduce waiting time of transplants
  • cells unlikely to be rejected by patient
  • many cells produced

  
• suggest two disadvantages of therapeutic cloning.

  • shortage of donors
  • egg donation has risks
• bone marrow cells differentiate into many types of blood cells, so will cure diseases where cells are damaged.

  
• Embryos advantages:

  • can create many embryos in a lab
  • painless technique
  • can treat many diseases

  Disadvantage

  • may not work
• Bone marrow advantages:

  • patient can give permission
  • can treat some diseases
  • reliable technique
  • patients recover quickly from procedure

  Disadvantages:

  • risk of infection from procedure
  • can only treat a few diseases
  • procedure can be painful
• embryos and bone marrow advantage:

  • can treat the disease

  disadvantage:

  • risk of transfer of viral infection
  • some stem cells become cancerous.