PCR test christmas test Flashcards
what is the purpose of a PCR test?
-it can create many copies of selected DNA in a very short time
what does PCR stand for?
-Polymerase Chain Reaction
what are the steps of the PCR test?
-DNA section heated to 95 degrees which breaks the hydrogen bonds to make it single stranded
-DNA cooled to 40-60 degrees which allows primers to bind to bind to each strand which are small strand that have complementary bases
-the primers jobs include stopping the DNA stands rejoining
-bracket the section of DNA that needs to be copied and they also stop DNA replication
-free nucleotides and DNA polymerase are are also added tp the strand
-the mix is heated again to 70 degrees
-DNA polymerase copies each strand, this polymerase is thermostable so it works rapidly at high temps
-the type of polymerase used depends on whether the dependence is on speed or accuracy of replication
-the two strand that are created are used as template strand to allow the process to continue again
when may the PCR test be used?
-forensic analysis
-medical research e.g. genetic screening and research reguarding genetic diseases
what are primers?
-short sections of DNA
-attach to the DNA strand to stop DNA replication, stop the strand rejoining and to bracket the section that needs to be replicated
