Replication of DNA Flashcards
The enzyme responsible for DNA replication
DNA Polymerase
What does this enzyme need to start DNA replication
Primers
What is a primer
A short strand of nucleotides which binds to the 3’ end of the template DNA strand so that DNA nucleotides can be added on
What does DNA polymerase do
DNA polymerase adds DNA nucleotides using complementary base pairing to the deoxyribose 3’ end of the new DNA strand which is forming
How many directions can DNA Polymerase add nucleotides
In one direction
What strand is continuously repeated
The leading strand
What strand is replicated in fragments
The lagging strand
What enzyme joins DNA fragments
Ligase
What happens after each cycle of PCR is completed
The number of molecules doubles.
What is the technique PCR used for
Used to replicate DNA outside the body. This process is used to amplify the DNA sample
What are PCR primers and how are they designed
Primers used in this process are complimentary to specific target sequences at the two 3’ ends of the region to be amplified. The primers are used one complementary strand to each strand
What enzyme plays an important role in PCR and what’s its function
Uses heat-tolerant DNA polymerase its function is to join nucleotides to the 3’ end of the new strand
What are three practical applications of PCR that require a small quantity of DNA to be amplified
Solve crimes
Settle paternity suits
Diagnose genetic disorders
What is set up before the thermal cycle
Target DNA is added to a test tube which contains heat tolerant DNA Polymerase, two types of primers and four types of DNA nucleotide
The first step of the thermal cycle
DNA is heated to between 93-98*C to separate the DNA strands
