Stem cells

• Stem cells are undifferentiated cells that have not yet specialised to perform a specific function. They can create more stem cells or differentiate (become another type of body cell) to perform a function.
• Embryos

  • The stem cells in embryos can differentiate into most cell types, to produce all of the cell types that will make up the organism.
• Plant meristems

  • Plant stem cells are found in the meristem tissue.
  • Plant stem cells can differentiate into all types of plant cell throughout the life of the plant. This allows plants to grow for their whole lives.
• Bone marrow

  • In human adults, stem cells can be found in bone marrow (as well as other tissues and organs).
  • Adult stem cells differentiate into fewer cell types than stem cells in embryos. They are used to replace dying cells and damaged tissues.
• Stem cells from human embryos can be cloned and made to differentiate into most different types of human cells.
• Stem cells from adult bone marrow can form many types of cells including blood cells.
• Meristem tissue in plants can differentiate into any type of plant cell, throughout the life of the plant.
• Treatment with stem cells may be able to help conditions such as diabetes and paralysis.