Recombinant dna tech Flashcards
What does recombinant dna technology do
Transfer of fragments of dna to another organism
What’s important about the genetic code
It’s universal aswell as transcription and translation mechanisms
What can the transferred dna do
Can be translated within the cells of the recipient
What’s a transgenic organism
-the organism with the transferred dna
Describe how reverse transcriptase works
Mrna acts as a template
- free dna nucleotides mix with mRNA and reverse transcriptase
- Complementary dna nucleotides line up along side mRNA
- DNA nucleotides join together creating a gene , using reverse transcriptase making cDNA
- Double stranded dna is produced from cDNA and nucleotides shinf dna polymerase
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What does the absence of introns mean
Fragments can be transcribed by bacteria
A gene obtained from restriction enzymes will have what
Introns in eukaryotic cells
Describe the gene machine
Production of dna fragments without needling pre existing dna or mRNA as a template
It’s an automated process
-the required nucleotide sequence is lrogrameed
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What does the absence of introns mean for the gene machine
-fragments can be transcribed by bacteria
When must introns not be present
If the source of a gene being transfrred is eukaryotic and the recipient of the fragment is prokaryotic
What is the main aim of promoter and terminal regiosns
Sections of dna must be added to the gene or dna fragment for successful transcription of transferred genes in recipient cell
What’s a promoter region
Initiate transcription of the gene by promoting the binding of RNA polymerase
What’s a terminator region
Marks the end of a gene and triggers the release of the MRNA transcribed
What does in vivo mean
Dna amplification where copies are made inside the cell
What’s in vitro
Copies of dna are made outside of the organism
How are genes transferred and what are they
Vectors
- plasmid in bacteria
-viruses
-liposomes
What is bacteria used for
- produce a protein coded for a transferred gene
- clone genes /fragments -
Why is bacteria chose for a clone fragment
- they divide very fast
Which enables the gene to be transferred quickly and quickly copied so large amount of gene
obtained
How is a plasmid cut
Using the same restriction enzyme as they have same recognition sequence (sequence of bases that restriction enzymes cut at )
What happens to plasmid when cut
The plasmid dna and foreign dna join by base pairing as complementary sticky ends
What is ligase
An enzyme used to form phosphodiester bonds
the dna on the nylon membrane is treated to from single strands why
so the radioactive dna probe can attatch to it
what are the ways of repeating or breaking down dna
-restriction enzymes
-gel electrpsis.
describe the relationship between primers and dna polymerase
-primers are short single strands of dna
- DNA polymerase is used to replicate and join strands of dna together
- for this to happen , Primers act as a starting sequence for dna polymerase to act on as primers are short strands of dna
