And we said that a special type of protein known as DNA helicase must bind to the origin of replication on the doublestranded DNA and this helps break the a hydrogen bonds that exist between our adjacent nitrogenous bases on our adjacent nucleotides. And this therefore unwinds and unzips our double stranded DNA and exposes the single stranded DNA molecule. So basically our DNA helicase binds to the origin of replication and as it moves it breaks the hydrogen bond and it unwinds our single stranded DNA molecules. And after we expose these sections another type of enzyme known as single stranded DNA proteins or simply SSB proteins bind to those exposed regions and they allow, they keep the two single strands from reassociating and reforming the hydrogen bonds. So these single stranded binding proteins are shown in green in this diagram. So once that takes place another enzyme known as DNA gyrase binds onto our double stranded DNA and it basically creates or introduces negative super coils and this decreases the stress that is involved with the process of unwinding.