DNA Replication

What is it?
DNA Replication is a process used to copy chromosomes inside the nucleas of a cell before the cell divides.
Where does it occur?
This process occurs inside the cell's nucleas.
When does it Happen?
The Replication of DNA occurs when before the cell can divide.
How Does it Happen?
1.DNA Replication begins with one double strand of DNA.
2.The Double strand helix is partially unwound by SSB Protiens and helicases into what is known as a replication fork.
3.As the two DNA strands unzip the run in anti-parallel directions.
4. DNA polymerase moves into position at the point where synthesis will begin. But since the Polymerase can only move from 5' to 3' direction the strands will replicate differently.
5.In the leading strand the Primase lays down the RNA primer.
6.Now the the RNA primer had been laid down Polymerase III builds a second strand in the same direction that the double helix is being opened.
7. In the remaining gaps more RNA primers attach yeilding Okazki Fragments (lagging strands)
8. RNA Primer stripped away DNA polymerase replaces with DNA nucleotides.
9. Ligase "glues" the remaining gaps in the sugar-phosphate backbone.



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