11 terms
DNA Replication
semi conservative model
two daughter molecules will have one old strand derived from parent molecule and one newly made strand
origin of replication
replication of a DNA molecule begins at these sites
helicases
enzymes that untwist the double helix at the replication forks
single strand binding proteins
after parental strand seperates binds to unpaired DNA strands stabilizing
topoisomerase
helps relieve this strain by breaking swiveling and rejoining DNA strand
dna polymerase
catalyze the synthesis of new DNA by adding nucleotides to preexisting chain
dna polymerase III
using parental DNA as a template synthesize DNA strand by covalently adding nucleotides to the 3' end of a preexisting DNA or RNA primer
dna polymerase I
removes RNA nucleotide of primer from 5' end and replaces them with DNA nucleotides
nuclease
DNA cutting enzyme -segment of strand containing damage is cut out
DNA polymerase and DNA ligase
enzymes that fill the gap when nuclease cuts out the damaged DNA
nucleotide excision repair
DNA repair system that use nuclease to cut out damaged strand and fills the gap with DNA polymerase and ligase