Recombinant DNA technology Flashcards
What is recombinant DNA technology?
the process by which genes are manipulated, altered, or transferred from organism to organism
What characteristic of the genetic code allows recombinant DNA technology to work?
universal
What is recombinant DNA?
DNA from two different sources that has been joined together
What is a transgenic organism?
has recombinant DNA
What are three ways of getting a fragment of DNA?
-convert mRNA into cDNA using reverse transcriptase
-cut gene from DNA using restriction endonuclease
-creating the gene in a “gene machine”
How can you amplify DNA?
using PCR
What are the two outcomes of using restriction enzymes?
-some cut straight across both strands forming blunt ends
-most make a staggered cut in the two chains, forming sticky ends
When can you use the “gene machine”?
when you know the primary structure of a protein
How does the “gene machine” work?
-amino acid sequence is entered into a computer
-the triplet code for each amino acid is known so the DNA sequence that will produce that protein is worked out
-the computer then controls the machine and the required DNA sequence is made
What is the promoter region?
it is attached to the DNA near a gene, is a binding site for RNA polymerase to start transcription and make a protein
What is the terminator region?
is added to the other end of the fragment to stop transcription by releasing RNA polymerase
What are 3 ways of transferring a vector to a cell?
-heat shock
-electroporation
-viruses
What are two ways of cloning DNA fragments?
-in vivo: transferring fragments to a vector
-in vitro: using PCR
What does PCR stand for?
polymerase chain reactions
Why are sticky ends important?
-when the same restriction endonuclease is used to cut DNA, all the ends of the fragments will be complementary to each other
-when two complementary sticky ends join up, DNA ligase can be used to join the sugar-phosphate backbone
What is used to transport DNA to the host cell?
a vector, like a plasmid, that often contains the gene for antibiotic resistance
When will the sticky ends be complementary?
when the restriction endonuclease used to cut the plasmid is the same as that which is used to cut the DNA into fragments
What does in vivo and in vitro mean?
in vivo = in the womb
in vitro = in glass/test tube/lab
What is complementary DNA?
DNA that is made from RNA in a process that is the reverse of normal transcription
What are restriction endonucleases?
enzymes used to cut DNA molecules
What are reverse transcriptases?
enzymes involved in copying an mRNA code into a DNA molecule
What are sticky ends?
ends of DNA fragments that have been cut with a restriction enzyme - can them be joined to a complementary cut piece of DNA
Name the 5 stages of DNA technology
-isolation
-insertion
-transformation
-identification
-growth/cloning
Explain how a piece of DNA could be isolated
-removes the DNA from its source
-such as adding a detergent, breaking down the cell membranes and freeing the DNA
-then digestive enzymes can be used to separate the specific gene wanted
