2.6B - Advantages and Disadvantages of stem cells in medicine

Edexcel IGCSE Biology - Topic 2

what are stem cells?

* undifferentiated cells
* can produce many more cells of the same type (undifferentiated stem cells)
* can undergo differentiation

embryonic stem cells

* found in inside layer of an embryo
* undifferentiated
* can produce all the different types of specialised cells in the body

adult stem cells

* found in bone marrow
* mainly differentiates into cells of the blood
* found in skin
* differentiates into cells found in layers of skin
* found in organs (liver, brain)
* differentiates into cells in particular orgain it is found in
* found in umbilical cord blood
* differentiates into cells of the blood, muscle tissue and nerve tissue

meristem cells

* found in the tips of roots and shoots in plants
* fully undifferentiated
* one stem cell = ability to produce whole new plant

what is stem cell therapy?

* used in medicine
* stem cells are injected into a damaged area and divide to form differentiated replacement cells
* this allows the organ to continue functioning normally
* sources of therapeutic stem cells: embryonic stem cells, umbilical cord stem cells

what are the advantages of using stem cells?

* could be used to cure many diseases in the future (diabetes type 1, paralysis)
* organs can be grown from patients own stem cells - reduces risk of rejection by body
* adult stem cells used successfully in variety of treatments

what are the disadvantages of stem cells in medicine?

* stem cells cultured in labs could become infected
* risk of culture stem cells accumalating mutations = risk of cancer
* low number of stem cell donors
* ethical issue of using embryonic stem cells from IVF - is it right to use them?
* embryonic stem cells/umbilical cord stem cells = expensive