Vectors
what is a restriction enzyme?
endonucleases break down the DNA of bacteriophages (invading viruses) and cut the sugar-phosphate backbone of the DNA to restrict a viral infection
what is a promoter?
region of DNA to which RNA polymerase binds to start transcription
What is genetic screening?
Genetic screening is analysis of a persons DNA to check for a specific allele
what is gene therapy?
replacing diseased genes by inserting normal genes in their place
What products are made from genetically modified plants that are beneficial to humans?
medicine, vaccines, albumin and proteins found in breast milk used for diarrhea in infants
How does making a plasmid vector work?
the circle of DNA is cut open using a restriction enzyme so that the sticky ends are complimentary then they are mixed together the DNA ligase is used to link the sugar phosphate back of DNA and plasmid which makes the double stranded DNA with the new gene (recombinant DNA)
What are the steps for gel electrophoresis?
the mixture of molecules is cut into agarose gel and applying an electric field and the results depends on the net charge, size of molecules, and composition of the gel.
what is the procedure for PGD (pre-implantation genetic diagnosis)
normal IVF procedure is first (mixing fathers sperm with mothers egg in a dish) then at the eight cell stage one of the cells form the embryo is removed and analyzed for genetic diseases that the parents are carriers for. Then the doctors would choose an embryo that didn't have the disease and use for implantation
what are the most common vectors for gene therapy?
retro viruses or lentiviruses and the occasional naked DNA
what are the advantages and disadvantages of herbicide-resistant crops?
Advantage - being able to spread an herbicide on a field and kill weeds rather than the plant
disadvantage- may become agricultural weed. pollen transfer to wild relatives that may make hybrid weeds. herbicide resistant weeds evolve to become resistant to same herbicide used
Getting the plasmids into bacteria. How is it done?
bacteria is marinated in calcium ions and given a heat shock to increase chances of plasmid through the cell surface membrane
what is the polymerase chain reaction?
method for rapid production of a very large number of copies of a fragment of DNA
what is amniocentesis?
Sample of amniotic fluid at 15-16 weeks to test for chromosomal mutations
How is cystic fibrosis caused?
The CFTR protein sits in the cell surface membrane of the alveoli and others to allow chloride ions to pass out of cells. The recessive cells code for this protein wrong and it doesn't function properly. Since it doesn't pump out the chloride ions the concentration builds outside, reduces water potential and leaving cystic fibrosis.
what is Bt toxin?
type of bacterium that is fused with the plant to make it insect resistant, different strains make the plant resistant to different insects, but harmless to animals that eat it.
how is insulin produced?
extracted mRNA for insulin from pancreatic B cells which are the only cells that express the insulin gene. The mRNA is marinated with reverse transcriptase from retroviruses. the single stranded DNA molecules using DNA polymerase for nucleotides and complimentary strands and makes amino acid sequences
What is different between gel electrophoresis of proteins and DNA?
Protein- ionization of R groups on amino acid residues
DNA- fragments move through the gel toward the anode and look at the VNTR using probes and a radioactive phosphorous isotope
what is chorionic villus sampling?
sample of amniotic fluid at 10-13 weeks that allows parents to get an earlier sign of any genetic abnormalities
what is the advantage of inserting DNA directly into tissues?
gets rid of the problems associated with vectors
How and why was golden rice produced?
It was made to deliver more nutrients to those living in poverty when their staple crop is rice. Scientists were able to insert more carotene into the endosperm of the rice to deliver more nutrients and bred to grow in places where poverty is high around the world.
what is a risk of antibiotic resistance?
what information is given in a microarray?
identify the genes present in a genome of an organism to find out the genes expressed within cells.
What is therapeutic abortion?
abortion due to a medical reason rather than any other such as Thalassaemia
what is germ cell gene therapy?
Instead of replacing the allele in somatic cells, but place them in germ cells so a woman with cystic fibrosis doesn't pass it to the child.
How was the Atlantic salmon genetically modified and why?
combining the growth hormone from Pacific Chinook salmon and promoter from another species of fish and injected into the Atlantic salmon so it can grow all year round and be used for fishing purposes.