DNA replication Flashcards
who discovered that the structure of DNA made it easy to replicate?
Watson and crick
(proven in 1958 by Mathew Meselson and Flranklin Stahl)
how does DNA replicate
semi-conservative
what type of strands will each daughter cell have?
one parent strand and one copy
how many replication orgins do prokaryotes have
One
what must DNA do before a cell can divide
create a copy of its self during mitosis or meosis
when does DNA replicate
during the S phase of interphase
how does DNA replicate in eukaryotes
- multiple replication orgins
- happens in both directions
replication bubble
when two replication forks are near eachother it forms a bubble
replication fork
where the two strands are still conected together while being seperated
what are to five DNA replication enzymes
- DNA helicase
- DNA gyrase
- DNA polymerase III
- DNA polymerase I
- DNA ligase
DNA helicase
unzips/ unwinds the double helix by breaking the hydrogen bonds between the nitrogenous bases
DNA Gyrase
relives the tension built up from DNA helicase
SSBP
single-stranded binding proteins
added by and enzyme to bind the sugar phasphate backbone. to each strand, every ssbp is the same charge so they rapel away from eachother keeping the strands apart so that DNA can replicate
DNA polymerase III
takes nucleotides and inserts them building the daughter strand, this causes the SSBPś to let go
- this enzyme will only move 5’ to 3’
Leading strand
strand of DNA that is orientated 5’to 3’
- built continuously
