1.2 - Replication of DNA Flashcards
What 2 factors are needed for the replication of DNA?
DNA Polymerase
Primers
What enzyme replicates DNA?
DNA Polymerase
What is a Primer?
A short strand of nucleotides, which binds to the 3’ end of the template DNA strand, allowing DNA Polymerase to add DNA nucleotides
How does DNA Polymerase add DNA nucleotides?
using Complementary base pairing
To which end does DNA Polymerase add new nucleotides to?
The deoxyribose 3’ end
What happens at the start of DNA replication?
DNA is unwound and hydrogen bonds between bases are broken to form 2 template strands
What happens once the DNA molecule is split into 2 separate strands?
DNA Polymerase adds DNA nucleotides in one direction (3’)
Which strands is replicated Continuously?
Leading strand
Which strand is replicated in fragments?
Lagging strand
Why are the 2 strands of DNA replicated differently?
DNA Polymerase can only add DNA nucleotides in one direction
What enzyme joins together the Okazaki fragments in the lagging strand?
Ligase
What does PCR do?
Amplifies DNA using complementary primers for specific target sequence
What happens at the first step of PCR?
DNA is heated between 92C and 98C to separate the strands
What happens at the second stage of PCR?
DNA is cooled down between 50C and 65C to allow primers to bind to target sequence
What happens at the third stage of PCR?
DNA is reheated between 70C and 80C for heat-tolerant DNA Polymerase to replicate the region of DNA
