Polymerase chain reaction Flashcards
What is a polymerase chain reaction?
A technique is used to amplify a section of DNA to produce multiple copies.
What are the 3 stages of PCR?
- Denaturing.
- Annealing.
- Extension.
Describe the denaturing stage of PCR.
Temperature is increased to 95 degrees to break hydrogen bonds. The enzyme helicase separates the two strands of DNA allowing each strand to be copied.
Describe the annealing stage of PCR.
Temperature is decreased to 50 degrees. This allows for primers to bind to the single DNA strands.
Describe the extension stage of PCR.
Temperature is increased to 72 degrees. This activates DNA polymerase. It attaches at the ends of the paired primers and moves along the single-stranded DNA adding complementary nucleotides.
List 5 ways PCR can be used.
- Detect harmful bacteria.
- Identify viruses.
- Paternity testing.
- Identify a species.
- Learn about an extinct species.
What is thermocycling?
A process of repeated heating and cooling.
What are primers?
A strand of DNA or RNA that serves as a starting point for DNA replication.
What is DNA polymerase?
Is an enzyme responsible for collecting nucleotides floating in the nucleus and matching them with the complimentary pairs on the parent strand.
