stem cells

• Stem cells


  Cells that can divide by mitosis to form more cells and can differentiate into specialized cells
• Stem cells


  • Can divide by mitosis to form more cells
  • Can differentiate into specialized cells
• Human life starts


  1. Sperm cell fertilizes egg cell

  2. Forms zygote

  3. Zygote divides by mitosis repeatedly

  4. Forms embryo

  5. Embryonic stem cells can differentiate into any cell type

  6. Cells continue to divide and differentiate

  7. Leads to baby after 9 months
• Embryonic stem cells


  Stem cells found in the embryo that can differentiate into any cell type
• Adult stem cells


  Stem cells found in adults that can only differentiate into a narrow range of cell types
• Adult stem cells


  • Stem cells in bone marrow that can differentiate into blood cells
• Plant stem cells


  Stem cells found in meristem tissues of plants that can differentiate into all the cells and tissues the plant needs
• Plant stem cells persist for the plant's entire life, unlike embryonic stem cells which disappear by the time we're fully developed
• Stem cells


  Cells that can divide by mitosis to produce more cells and can differentiate into different types of specialized cells
• Types of stem cells

  • Embryonic stem cells
  • Adult stem cells
• Embryonic stem cells


  • Found in the early embryo
  • Can differentiate into any type of specialized cell
• Adult stem cells


  • Found in the bone marrow
  • Can only differentiate into different types of blood cells
• Many conditions are due to faulty cells that are damaged or don't work properly
• Using stem cells to treat conditions

  1. Extract stem cells

  2. Grow them in a lab

  3. Stimulate them to differentiate into desired cell type

  4. Transplant into patient
• Conditions that could be treated with stem cells

  • Diabetes
  • Paralysis
  • Sickle cell anemia
• Drawbacks of using embryonic stem cells

  • Limited supply
  • Ethical issues
  • Risk of rejection by patient's immune system
• Advantages of using adult stem cells

  • Easy to obtain
  • No risk of rejection
  • Limitation to blood cell types
• Potential risks of using stem cells include virus transmission and tumor development
• Ethical objection to using embryonic stem cells

  Embryos have potential for human life
• Embryos used for research are usually unwanted from fertility clinics that would otherwise be destroyed
• Stem cell research is tightly regulated in the UK with strict rules for scientists to follow