Lecture 21 Flashcards
1
Q
Who invented PCR?
A
Kary Mullis in 1970s
2
Q
PCR is based on 2 key concepts, which ones?
A
- When DNA is expose to high temperatures, the hydrogen bonds that hold the two strands together will break, giving 2 single strands of DNA.
- Extremophiles live and can carryout cellular processes at very high temperatures.
3
Q
What is DNA polymerase?
A
the enzyme responsible for copying the sequence starting at the obligonucleotide primer from the single DNA strand
4
Q
What is PCR?
A
it is an in vitro technique for the amplification of a region of DNA which lies between 2 regions of known sequence
5
Q
At which cycle does the target DNA appears?
A
at the third cycle
6
Q
PCR grows…
A
exponentially
7
Q
What do you need to carry out PCR?
A
- template DNA
- free nucleotides
- heat stable polymerase
- thermocycler
8
Q
What are the 3 steps of PCR?
A
- Denaturation: the DNA samples are heated at 95°C and denatured
- Annealing: the temperature is cooled (45-54 °C) and the primers anneal to the specific region
- Extension: Taq polymerase extends the DNA (72°C) thus giving new copies of the DNA
www.youtube.com/watch?v=iQsu3Kz9NYo
9
Q
PCR cannot amplify large amounts of DNA, only used on smaller specific regions such as genes (10,000 bp)
A
true
