1.2 - Replication of DNA Flashcards
when does replication of DNA take place?
prior to cell division
what enzyme replicates dna?
dna polymerase
what is needed to start replication
a primer
what is a primer?
a short strand of nucleotides
where does a primer bind?
the 3’ end of the template strand
what does a primer allow?
dna polymerase to add dna nucleotides
what method does dna polymerase use to add dna nucleotides to the 3’ end of the new strand?
complimentary base pairing
what is done to the original piece of dna before it is able to be copied and what does it form?
it is unwound and the hydrogen bonds between bases are broken forming 2 template strands
the leading strand is replicated ………
continuously
the lagging strand is replicated in ……..
fragments
what characteristic of dna polymerase means it can only add nucleotides in one direction?
it can only add nucleotides to the 3’ end of the deoxyribose sugar
how are the fragments of the lagging strand joined together
using ligase
in pcr, primers are short strands of nucleotides which…
are complementary to specific target sequences at the 2 ends of the region of dna to be amplified
what are the 3 temperatures of pcr stages
93, 63, 73
dna is heated to 93 to …………………
separate the strands
dna is cooled to 63 to……………
allow primers to bind to their target sequences
dna is heated to 73 for …………………..
heat tolerant dna polymerase to replicate the region of dna
pcr is used to do what to dna?
amplify it
what are the practical uses of pcr
solving crime, settle paternity suits, diagnose genetic disorders
