Biotechnology Flashcards
how are specialized tissues developed?
- developed by cell differentiation in multicellular organisms
- differentiated cells only express some genes
- undifferentiated = stem cells
what is special about stem cells and why are they useful?
- capacity of stem cells to divide + differentiate along different pathways necessary in embryonic development
- this makes them suitable for therapeutic uses
what are the 3 types of stem cells? and describe pros and cons of each
- embryonic: taken at embryonic stage, big potential, larger tumor risk, less genetic damage, ethical issue
- adult (tissue specific): more specific (bone marrow), difficult to obtain, less tumors, more genetic damage, fewer ethical issues
- cord blood: taken at birth, stored for later used, limited use, equity concerns
what are induced pluripotent cells?
- autosomal cells that revert to stem cell status
- highly coiled DNA told to uncoil by certain genes, making DNA available for expression.
provide examples of therapeutic stem cell use
- skin tissue for burns, type 1 diabetes, spinal cord
- grown replacement organs
- embryonic stem cells can stimulate development of retina cells for Stargardt’s disease
- bone marrow stem cells to treat leukemia.
what is gel electrophoresis used for?
- separate proteins or DNA according to size
- DNA molecules are negative so will move down the gel creating different patterns
describe the steps of PCR
- can quickly make many copies of impure DNA, highly automated
- 1st heating up to separate DNA strands (95 degrees F)
- 2nd cool down and allow DNA primers to attach along each end of target sequence (54 degrees F)
- 3rd is extension of DNA in 5’ to 3’ direction by DNA polymerase
what are some uses for PCR?
DNA from extinct species, finger printing, diagnosis of genetic diseases and COVD, DNA of viruses
what does DNA profiling involve?
- DNA from various suspects processed by PCR
- DNA cut using restriction enzyme (endonuclease)
- gel will create patterns, and compare DNA
how is DNA profiling used for paternity testing?
children inherit 1/2 of chromosomes from each parent, therefore they have a combo of parental fragments: these are compared
how is genetic modification carried out? (4 steps)
- genes can transfer from one organism to another because genetic code is universal
- 1: isolate the gene through PCR or mRNA, isolate vector (gene used to carry gene of interest into cell) often by bacterial plasmids
- 2: gene and vector cut at recognition site leaving sticky ends in sugar phosphate backbone to ensure orientation + prevent re-aneiling
- 3: cut gene inserted into plasmid using overlapping complementary bases and spliced together using DNA ligase
- 4: gene structure introduced into host cell or organism
what are the pros and cons of GMO’s in crops?
Pros:
- added nutritional value
- lack allergens
- drought resistance
- crops produce herbicides
- improve supply
- longer shelf life
- lower cost
Cons:
- potential health reactions
- unknown effects
- limit biodiversity
- cross pollination + super weeds
- patents restrict farmers
- not labeled
describe the steps of cloning using a somatic cell
- 1: the nucleus of an egg cell from one organism is removed
- 2: a somatic cell is removed from donor (diploid with whole genome)
- 3: enucleated egg cell fused with adult donor nucleus to make diploid egg cell
- 4: electric current to stimulate egg cell to divide/develop into embryo
- 5: embryo implanted into uterus of surrogate
what are clone?
groups of genetically identical organism derived from a single original parent cell
examples of natural clones?
twins, garlic cloves, potatoes, strawberries, hydra, female aphids
