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Cell division - AQAUsing human stem cells

Chromosomes carry genetic information in a molecule called DNA. A type of cell division called mitosis ensures that when a cell divides each new cell produced has the same genetic information.

Part of Biology (Single Science)Cell biology

Using human stem cells

Stem cells can divide to produce new cells, which can then divide into different cell types. They therefore have the potential to be transplanted into patients to treat medical conditions and . They could be used to replace cells that have been damaged or destroyed, eg:

  • in type 1
  • in cases of , which can lead to
  • in cases of or injury, that have led to paralysis

The stem cells used could be:

Embryonic stem cells can differentiate into a wider range of cell types, but are difficult to obtain and their use raises ethical challenges. The best source is the five-day-old embryo.

Adult stem cells will differentiate into a narrower range of cell types. Bone marrow transplants are an example of adult stem cell transplant. Bone marrow cells will differentiate into different types of blood cell. Bone marrow transplants are carried out:

  • in cases of blood cell such as leukaemia and lymphoma
  • when blood cells have been destroyed by cancer treatment