Biotechnology 2 Flashcards
what is the definition of recombinant DNA?
the process of introducing DNA into a cell from a different type of organism or DNA that has been modified in some way
what is a genetically modified organism ?
a organism produced by genetic engineering
what is a transgenic organism?
an organism that has had DNA from another species introduced into it artificially
how is DNA cut?
using restriction enzymes
where do they cut the DNA?
-It is cut at the recognition site
what does DNA ligase do ?
joins the phosphate group at the end of one strand to the sugar molecule at the end of another strand
what is the process of recombinant DNA?
- gene is isolated and cut using a restriction enzyme
- isolate a plasmid and cut it with the same restriction enzyme
- use DNA ligase to splice the gene into the vector
4.treat the bacterium so that the recombinant DNA is taken up into the cell - bacteria is left to divide and produce clones
- bacteria will now be able to produce the protein using the donor DNA.
what is gene therapy?
the use of genetic material to treat or prevent disease
what is In Vivo?
when the gene is directly inserted into the person
what is Ex Vivo?
cells are taken out of the body the gene is inserted into the cell and then put back into the body
what is the process of using gene therapy as a form or treatment for diabetes?
- virus containing protein is inserted into the pancreas
- these proteins change gene expression and cause alpha cells to produce insulin
- these new “beta cells” are resistant to attack by T-cell as they are slightly different to regular ones
- this would not be a lasting ‘cure’ and has been shown to work for 4 months in mice
what is cell replacement theory ?
replacing damaged cells with stem cells could be a treatment for any disordes involving loss or injury of normal cells
what is Parkinsons disease?
results from damage to the nerve cells that produce dopamine a chemical that is vital for the smooth control of muscles and movement
what is Alzheimers disease?
characterised by changes in the brain that leads to deposit of proteins and loos of connections between neurons.
how is cell replacement theory used for a potential treatment of degenerative disease?
- potential to grow stem cell into new neurons to replace damaged ones (wouldn’t prevent the cells from dying)
-stems cels from embryos may be used (ethical issue)
-clinical trails transplanting young brain cells from foetus into people with parkinsons (ethical issue)
-scientist can now make dopamine
where can DNA profiling be used?
Anthropology research
establishing an individuals identity
detecting genetic variation
what do restriction enzymes do ?
they are added to DNA to cut the strand of DNA into different lengths depending on base sequence
what is gel electrophoresis?
the technique of separating strands into their lengths
what is the process of gel electrophoresis?
1.The DNA pieces are placed in wells in a semi-solid gel that is immersed in a buffer There are electrodes at either end of the gel. The negative electrode is closest to the DNA
2. When an electric current is passed through the gel, the negatively charged DNA moves towards the positive electrode.
3. The smaller DNA pieces move faster than the larger ones and so are located further away from the negative electrode when the current is stopped.
what is DNA sequencing?
determining the precise order of nucleotides in a sample of DNA
what is a overview of DNA sequencing?
- a synthetic nucleotide is added called dideoxynucleotide triphosphate that results in no more phosphates being able to attach to the OH group this allows for different lengths of DNA
what is DNA sequencing used for?
- identify mutation
- compare dna
- compare species in order to track evolutionary changes
is DNA sequencing ethical?
NO
-autonomy
-confidentiality
-equity
-privacy
why can comparative genomics occur?
- specific proteins will have the same sequence
- when speciation occurs the new species have very similar DNA to the original species
-over time species gradually change giving more DNA changes
how can DNA be used as evidence for evolution ?
- the more similarities in the DNA code between two species the more closely related they are
- the more differences in the DNA code between two species the more distantly related they are
what is junk DNA?
the non-coding sequence of the bases in DNA
what is an endogenous retrovirus
non-coding sections of DNA but the RNA genome is copied into DNA in reverse transcription and is only endogenous if inherited by the next generation
how are ERVs used for evidence for evolution?
any retrovirus that has been inserted into the genome of a common ancestor would be inherited to the next species in the same spot.
what is mitochondrial DNA?
DNA that is located in the mitochondria
it is only inherited by from the maternal side
5-10 circular DNA
how is mitochondrial DNA used for evidence for evolution?
- it has a higher rate of mutation
- the mutations are proportional to the length of time that has passed
more mutation more time has passed
less mutation less time has passed
what is protein sequencing ?
-there are 20,000 different proteins but only 20 different amino acids
-can be compared by similar proteins between species by looking at the sequence of amino acids
how can protein sequencing be used for evidence for evolution?
more differences the more distantly related to the common ancestor
the less differences the more closely related they are to a common ancestor
what is a ubiquitous protein?
protein which are present in all species and carry out the same function
what is bioinformatics?
using computer technology to collect, store, analyse and disseminate biological data and information
what is annotation?
the computerised process that identifies the location of genes and all coding regions of a genome
