Stem Cells - In-depth Flashcards
Stem cell
cells that have:
- the ability to divide and
- produce different types of cell
How many types of stem cells do animals have
Animals have two types of stem cell
Adult stem cells
Adult stem cells that can:
- divide to form cells of the same general type,
- e.g. stem cells in the bone marrow only form the different types of blood cell
Embryonic stem cells
Embryonic stem cells from embryos or the umbilical cord can form the full range of cells in the body
Where embryonic stem cells are found
- embryos
- umbilical cord
What do animal stem cells develop into after a number of divisions?
specialised cells which are adapted for particular functions, Ec.g. nerve cells.
Where stem cells are found
meristems
- (the rapidly dividing zones at shoot and root apices, or tips).
What do plant stem cells do after a number of divisions?
- retain the ability to divide
- can be used in cloning techniques
Uses of stem cells in medicine
Bone marrow transplants
- leukaemia
Bone marrow transplants
The stem cells in the bone marrow from a donor contain the ability to produce the different types of blood [cell in the right proportions (which doesn’t happen in leukaemia).
Leukaemia
type of cancer of the blood
Potential benefits of embryonic stem cells
• Diseases such as leukaemia can be treated
• Replacement of body parts, including replacement organs
Potential risks and ethical considerations of embryonic stem cells
• With leukaemia pre-treatment can involve radiotherapy and/or chemotherapy, which can kill healthy cells as well
• The transfer of viruses or diseases from other animals
• Formation of tumours or the development of unwanted cell types
Peer review
- scientific research is checked by other scientists of at least equal standing
What does scientific research need to be
Validated
