Polymerase Chain Reaction (PCR) Flashcards
(6 cards)
1
Q
Name the requirements for PCR
A
- DNA : the original strand which needs to be amplified
- Complementary primers: primers are short complementary sequences of RNA needed to start DNA synthesis
- Thermal cycler: equipment that varies the temperature of the reaction
- Heat tolerant polymerase: an enzyme which will add nucleotides to the growing strand and not be denatured by the high temperatures
- Supply of free nucleotides: to synthesise new strands of DNA
2
Q
What happens during the first stage?
A
The DNA is heated above 90*C to break the hydrogen bonds between the bases, unzipping the molecule
3
Q
What happens during stage 2?
A
DNA is cooled in preparation for the primers being added
4
Q
What occurs in stage 3?
A
Complementary primers are added which are complementary to the target sequences at the two ends of the region to be amplified.
5
Q
What happens during stage 4?
A
Heat tolerant DNA polymerase is added which replicates the regions of DNA to be amplified. Two strands are formed.
6
Q
What happens during stage 5?
A
Repeated cycles are carried out which amplifies the desired strand of DNA into millions of copies
