B2.3 Cell Specialisation Flashcards
Stem cells are cells that:
Retain the capacity to divide
Have the ability to differentiate along different pathway
stem cell niche
location that the stem cells are present in high numbers
This is a result of proliferation, and they also demonstrate differentiation
E.g. Bone marrow, hair follicle
type of stem cells
totipotent
pluripotent
multipotent
unipotent
totipotent
Able to differentiate to _all cell types e.g., embryonic stem cells.
pluripotent
Able to differentiate to almost all cell types but cannot produce a complete organism. e.g., embryonic stem cells.
multipotent
Able to differentiate to limited cell types. e.g., adult bone marrow stem cells.
unipotent
Can only form a single cell type. e.g., sperm cell
Stem Cell Therapy
Stem cells can be used to replace damaged or diseased cells with healthy, functioning ones.
This process requires:
The use of biochemical solutions to trigger the differentiation of stem cells into the desired cell type
Surgical implantation of cells into the patient’s own tissue
Suppression of host immune system to prevent rejection of cells (if stem cells are from foreign source)
Careful monitoring of new cells to ensure they do not become cancerous
stem cell therapies example
Stargardt’s Disease
Parkinson’s Disease
stargardt’s disease
An inherited form of juvenile macular degeneration that causes progressive vision loss to the point of blindness
Caused by a gene mutation that impairs energy transport in retinal, causing them to degenerate
Treated by replacing dead cells in the retina with functioning ones derived from stem cells
parkinson’s disease
A degenerative disorder of the _central nervous system__caused by the death of _dopamine-secreting _ cells in the midbrain
Dopamine is a neurotransmitter responsible for transmitting signals involved in the production of smooth movements
Consequently, individuals with Parkinson’s disease typically exhibit tremors, rigidity, slowness of movement and postural instability
Treated by replacing dead nerve cells with living, dopamine-producing ones
Other Therapeutic Examples
luekemia
diabetes
luekemia
bone marrow transplants for cancer patients who are immuno-compromised as a result of chemotherapy
diabetes
Replace non-functioning islet cells_with those capable of producing insulin in type I diabetics