1.1 Cell Specialization Flashcards
Stem Cells
Unspecialized cells
2 key qualities of stem cells
Self Renewal
Potency
Self Renewal
Can continuously divide and replicate
Potency
Have the capability to differentiate
4 main types of stem cells
Totipotent
Pluripotent
Multipotent
Unipotent
Totipotent
Can form any type of cells and EXTRA embryonic TISSUE
Pluripotent
Can form any type of cell (like embryonic stem cells)
Multipotent
Can differentiate into closely related cell types
Unipotent
Can NOT differentiate but are capable of SELF RENEWAL
Adult Stem cells are what?
Unipotent and mulitpotent
Fetal stem cells may be…
Multipontent or pluripotent
Embryonic stem cells may be…
Pluripotent or totipotent
Stem cells can
replace damaged or diseased cells with healthy ones
Therapeutic procedure of stem cells
- Harvesting stem cellls
- Using biochemical solutions to trigger cell differentiation
-Surgically implanting news cells into patients
- Suppressing host immune system to prevent rejection
- Monitoring new cells to ensure nothing is cancerous
Therapeutic Example
Stargardt’s Disease
Parkinson’s Disease
Leukemia
Stargardt’s Disease Condition
Macular degeneration
Stargardt’s Disease Treatment
Replace defective retinal cells
Parkinson’s Diease Condition
Death of nerve tissue
Parkinson’s Disease Treatment
Replace damaged nerve cells
Leukemia conditions
Cancer of the blood
Leukemia Treatment
Replacement of bone marrow
Ethics of Stem Cell Use in EMBRYO
Growth Potential: High (pluripotent)
Tumor Risk: Higher
Harvesting: Can be generated artificially by SCNT
Disadvantages of Embryo
Requires destruction of the embryo.
(Results in the loss of a potential)
Ethics of using umbilical cord blood
Growth potential: Low (multipotent)
Tumor Risk: Low
Harvesting: Easily obtained and stored. Preserved
Disadvantages of Umbilical Cord Blood
Cells must be stored from birth at cost
–Raises issues of financial accidentally
Ethics of Adult Tissue
Growth Potential: Low (multipotent)
Tumour risk: Low
Harvesting: Invasive to extract
Disadvantages of Adult Tissue
Maybe be restrictions in scope/availability
Differentiation
The expression of some genes and not others in the cell’s genome (selective gene expression)
Cell Specialization
The activation of different genes within a given cell will cause it to develop differently
Active genes loosely packed
Euchromatin
Inactive genes are packed tight
heterochromatin
