-DNA replicate semi-conservatively. During DNA replication, base pairing enables existing DNA strands to serve as templates for new complementary base pairs.
-On each of the upper and lower strand will have many lagging and leading strand. To be more specific at each replication bubble there is one lagging and one leading strand on the DNA itself.
Replication Enzymes
DNA Helicase Primase-RNA Primer DNA polymerase I Single Stranded Binding Protein
DNA Polymerase III DNA Ligase DNA Gyrase
1) DNA Helicase- Unwind the double helix by breaking the hydrogen bonds between complenmentary base pairs that hold DNA strand together.
2) Gyrase- Massage the unwinding DNA to release any tension.
3) Single Stranded Binding Protein- Bind to exposed single stranded DNA and block hydrogen bonding to prevent the two strand of DNA anneal back.
4) Primase- is an enzyme synthesis RNA Primer, which is the initiation sequence for replication.
5) Polymersase III- build complementary strand using the template strand/ catalyze the elongation of new DNA at a replication fork/grab deoxyribonucleoside trisophate as new strand building up using the template strand. As it is add from the 3' to 5' the leading strand will replicate continuously and the lagging strand will replicate along with the unzipping process of DNA. On the lagging strand there are many different fragments of replicated DNA, Okazaki fragments, from 3's to 5's due to the prevention of degration of DNA.
6) Polymerase I- remove the RNA Primer from the replicated DNA of the leading and lagging strand. And replace these RNA Primers with appropriate deoxyribonucleotides.
7) Ligase- act as glue to join the Okazaki fragments of the lagging strands and gaps between pieces of DNA at the end of replication fork.
8) Polymerase I & Polymerase III- proofread the finish replicated DNA.
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