Stem Cells Flashcards
What are stem cells?
Cells that are unspecialised and capable of differentiating into a range of different cell types.
What is meant by ‘Differentiation’?
•The process by which stem cells become specialised (have a specific function).
•Some genes switch on and off, determining cell types.
Why is cell differentiation important?
Enables the formation of specialised tissues with specific functions e.g. muscle tissues.
What are embryonic stem cells?
Stem cells found in very early embryos that are unspecialised and capable of differentiating into any cell type.
What is the function of embryonic stem cells?
Enables the growth and development of tissues in human embryos
Where can embryonic stem cells be collected from?
•Donor stem cells removed from embryos grow in vitro.
•Patients own stem cells removed from the umbilical blood before birth.
What are adult stem cells?
Stem cells that can differentiate into a limited range of cell types; e.g. bone marrow stem cells.
What is the primary function of adult stem cells?
Replacement of dead cells e.g. replacements of red blood cells which only live for 120 days.
Describe the potential uses of stem cells in medicine
•Treat disease e.g. heart disease, type 1 diabetes.
•Used to repair damaged tissue e.g. brain damage.
•Used in scientific research.
•Growing organs for transplants.
What are the ethical issues related to the use of stem cells in medicine?
•The embryos used to provide stem cells are destroyed which is seen as unethical and a waste of potential human life.
•Could lead to the ‘farming’ of embryos for stem cells.
•May lead to the reproductive cloning of humans.
Where are stem cells found in plants?
Meristems
Where is meristem tissue found?
In regions of the plant where cells are continuously dividing, e.g. root tips, shoot tips.
