Genetic Engineering Flashcards
Describe how genetic engineering could be used to modify(object/food)
1) isolate the gene for(..)from…
2) use restriction enzyme to create sticky ends
3) insert gene in to plasmid vector
4) DNA ligase to join sugar phosphate backbone forming the recombinant plasmid
5) insert gene in to plasmid
6) with a promoter gene so gene can be expressed
7) place in to needed cells
What enzyme is used to cut the DNA
Endonuclease
Why is a plasmid vector used
Replicate fast
Circular so stable
Have marker genes so recombinant can be recognized
Outline the steps of the PCR
1) DNA is denatured by heating giving 2 strands and exposing the bases(heat to 95 degrees)
2) the DNA polymerase enzyme is used to make new strands of DNA using the old ones as templates
3) DNA primer complimentary to the strand of the DNA strand is used to attach to it(anealing heat to 65 degrees)
4) this allow the DNA polymerase to bind and start adding nucleotides to it(elongation heat to 72)
5) the mixture with the copied DNA is the heated again and the steps repeated over and over
6) Taq polymerase is used
What does movement of molecules in gel electrophoresis depend on
1) net change,the higher the charge the faster the movement
2) Size smaller molecules moves faster
3) Composition of the gel polyacralmide for proteins agros for DNA
Why are DNA fragments -vely charged
Due to the phosphate groups
What are DNA probes
Short lengths of DNA made of
1)radioactive phosphorus isotope and so strains appear on c ray film
2)labelled with flour-scent stain that glows in UV light
This makes the DNA bands visible
Where do molecules of normal Hb move towards
Anode
What is bioinformatics
Collection,processing and analysis of biological information using computer software
It forms a data base for gene sequence and sequence of whole genome
What is cystic fibrosis
A genetic disorder where thick dehydrated mucus is produced in the lungs and other parts of the body such as the pancreas duct,oviducts and sperm ducts
What are the causes of CF
Recessive allele for the gene which codes for transmembrane protein CFTR
Normal CFTR allows cl- to pass out of the cells by active pumping
This increases the water potential of the cells allowing water to move out by osmosis to dissolve this mucus
Which chromosome is the CFTR gene found on
7
What are the dis of GM food production
1) GM crop plant may become agricultural weed or invade habitat
2) Introduced gene transferred by pollen and contaminate organic crops
3) GM plants may be a direct hazard to humans by being toxic or allergic
4) Herbicide that is now used on crop can leave toxic residue on it
5) GM seeds are expensive and their cost may remove Any adv of growing them
6) Growers need to buy seed each year
Microarrays essay
Micro chip slide with many slots arranged in numbered columns and rows
Each lot has several copies of the same DNA probe of a specific gene
All these gene positions are stored in a database of computer
Extract MRNA from the cell
Incubate it with reverse transcriptase enzyme and red florescence labeled DNA nucleotides
It makes a single strand of complementary DNA which enters the PCR to be amplified
Load complementary DNA into buffer solution using a micro Pippette onto a microchip
Complementary DNA hybridize with DNA probes on micro chips
As complementary bases pair and bind together under ultraviolet light
black spot indicates gene is not expressed in this cell
red spots indicate Gene is expressed
Discuss the ethical implications of IVF
Not natural Multiple births Possible birth defects Cost to health service Some embryos discarded Unknown effects of freezing embryo for storage Issues regarding use of stem cells Issues regarding selection of gender Physiological side effects
