How does Polymerase Chain Reaction work?

Answer 1

Polymerase chain reaction, or PCR, is a laboratory technique used to make multiple copies of a segment of DNA. PCR is very precise and can be used to amplify, or copy, a specific DNA target from a mixture of DNA molecules.

Answer 2

You put in DNA that you want replicated into a buffered solution containing all four nucleotides (AGCT), add primers and Taq Polymerase. Heat to denature the DNA into seperate strands. Then the polymerase will anneal the primers and extend (duplicate the sequence) as cools. Heat... repeat...heat... repeat...etc etc etc until you have as much DNA as you need. 25-35 cycles is usually enough to produce all the DNA you need for most other applications.

Answer 3

The DNA fragment is placed into a thermocycler at 95°, this temperature breaks the hydrogen bonds between the double stranded DNA fragment. The thermocycler is then cooled to 55°, this temperature allows primers that are added to anneal to the starting sequences of the two strands of DNA. Primers allow DNA polymerase to function. The thermocycler is then heated to 72°, where DNA polymerase is added. DNA polymerase then anneals nucleotides that are added to the template strands of DNA. Each cycle produces double the DNA that was inserted initially.