PCR Flashcards
Polymerase Chain Reaction (16 cards)
What is the definition of Polymerase chain reaction ?
a technique for replicating specific DNA sequence outside the cells.
What is the purpose of PCR ?
A small amount of DNA sample can be amplified to many copies quickly and accurately.
What is the principle of PCR ?
It relies on the structural change of DNA double-strands under different temperatures.
The PCR machine used follow a what cycle ?
Thermal cycle.
What are the process of PCR ?
(1) denaturation
(2) prime annealing
(3) extension
(4) amplification of DNA
(5) purification
What temperature should each step be carried out ?
Denaturation: 90C
Prime annealing: 55-65C
extension: 70C
What is the purpose of denaturation ?
(1) break hydrogen bonds
(2) unwinds double helix
(3) each strand serve as template strand
What is the feature of the two DNA strand that serves as template strand ?
They are antiparallel.
What is the purpose of prime annealing ?
(1) mark selected DNA region to be amplified
(2) allows primer to anneal the single-stranded DNA by complementary base pairing
What is the purpose of extension ?
(1) raising temperature to 70C for heat stable DNA polymerase
(2) Use DNA polymerase to add nucleotides to new strands
What components are required to carry out PCR?
(1) DNA template
(2) nucleotides
(3) a pair of primers
(4) DNA polymerase
(5) MgCl (co-factor to DNA polymerase)
How the thermal cycle helps the amplification of DNA ?
(1) amplification can be done automatically
(2) PCR can be done in a short time
Why is Taq DNA polymerase used and enables thermal cycling of PCR ?
(1) DNA polymerase was easily denatured at high temperature
(2) Taq DNA polymerase is heat-stable
(3) reduce cost and time of procedure
State two properties of PCR
(1) PCR is fast and accurate
(2) PCR is highly sensitive
How can we check if the amplified product has the same size as our expectation ?
By Gel Electrophoresis
Give some applications of PCR.
(1) Detection of GM foods
(2) Detection of genetic disorder
(3) Human Genome Project
(4) Medicine
(5) DNA fingerprinting
(6) Archaeological study
