What is PCR?
How does PCR work?
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Illustration showing the main steps in the polymerase chain reaction (PCR). What happens at each stage of PCR?Denaturing stage
Annealing stage
Extending stage
Illustration showing how the polymerase chain reaction (PCR) produces lots of copies of DNA. This page was last updated on 2021-07-21 What is the role of the 72 degree phase in PCR?The final stage is the extension step (20 sec to 1 min at 72 °C), which is performed so that the DNA polymerase extends the primer sequences from the 3' of each primer to the end of the amplicon.
What happens at 72 degrees in a thermal cycler?Gradually the temperature begins to cool to 50 degrees Celsius so the primers will attach. Then the temperature is raised to 72 degrees DNA polymerase is activated and locates primers attached to the single-strand DNA, which will then begin to add complementary nucleotides onto the strand.
Which enzyme is active at 72 degree in the polymerase chain reaction?Taq DNA polymerase is the most common enzyme used for PCR amplification. This enzyme is extremely heat resistant with a half-life of 40 minutes at 95°C. At its optimal temperature (72°C), nucleotides are incorporated at a rate of 2–4 kilobases per minute.
Why does the temperature need to be raised to 72 C after the primers have bonded to the DNA strand?Extending stage. During this final step, the heat is increased to 72⁰C to enable the new DNA to be made by a special Taq DNA polymerase enzyme which adds DNA bases.
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