Gene technology Flashcards
Cut plasmids unless a foreign DNA can join what features of the ends allow them to join?
Sticky ends that are complementary
Some human DNA was cut into separate pieces using a restriction enzyme which are producing a staggered cut. The scientist wanted to insert these pieces of DNA into a plasmid and use the same restriction enzymes to cut their plasmids. Explain why the piece of human DNA would be able to join to the cut of DNA of the plasmid
sticky ends with reference to complementary base pairing
Plasmid maybe use a vector explain what is meant by effect in this context
Carrier of DNA into a another organism
biologist often use plasmids which contain antibiotic resistance genes explain reason for this
acts a marker gene allows detection of cells containing plasmid
Describe how the geneticist would attempt to insert copies of the HGH into these plasmids
Cut the plasmid with restriction endonuclease
So that both have complementary sticky ends
Mix together and add ligase to join the complementary sticky ends
Hepatitis B vaccine contains a viral antigen produced by genetically modified bacteria. Describe how the isolated gene that codes for a protein in the viruses coat could be transferred into the bacterial cells
Restriction enzyme
To cut plasmid to form sticky ends in plasmid
Use like ligase to join gene to plasmid
Culture bacteria with plasmids
To allow uptake of plasmids
Use a cold shock/chemical treatment/ heat-shock
Using the information given explain how the use of a gene probe could enable the presence of a mutant allele of cystic fibrosis gene to be detected
Probe will attach to mutant allele; attaches to one DNA strand; as a result of complementary base pairing; radioactivity detected on film if mutant allele present
What is meant by gene therapy?
Introduction of a healthy gene
Individuals have been treated with the method of gene therapy do not pass on the ADA to the children explain why
Gamete cells do not contain ADA Allele
explain why treatments of ADA deficiency by Gene therapy must be repeated at regular intervals whereas a single bone marrow transplant can provide a permanent of cure
T lymphocytes have limited lifespan
bone marrow provides continuous supply of T lymphocytes ADH gene
Describe how a gene could be removed from cells of a amaranth plant and inserted into the cells of a potato plant
Cut out gene using a restriction enzyme at
specific recognition sites
Sticky ends
Use the same enzyme to cut plasmid
Fixed by ligase
Method of introducing vector- virus in injects DNA
Remove plant cell wall
Whole potato plants can be produced from genetically identical potato cells grown in a tissue culture
Use your knowledge of genes to suggest how different cells such as a lead and root cells can develop from genetically identical cells
Different genes are expressed
Plasmids can be modified by genetic engineering and inserted into bacteria. These bacteria can then make useful substances normally made by other organisms. Explain how modified plasmid and made by genetic engineering and how do use of markers enable bacteria containing these plasmids to be detected
Isolate wanted gene from another organism
Use restriction enzyme
Produce sticky ends
Use ligase to join wanted gene to plasmid
Also include marker gene e.g. antibiotic resistant
Add plasmid to bacteria to grow colonies then played onto medium where the marker gene is expressed
Colonies not killed have antibiotic resistance gene and probably the wanted gene
Describe how a gene can be isolated from human DNA
use restriction enzyme
To cut DNA in specific place
Describe how an isolated gene can be replicated by PCR
Heat DNA to 90–95° Strands separate Add primers Add nucleotides Cool so that primers bind to DNA DNA polymerase forms new strands/ join nucleotides
