DNA Replication

DNA Replication 

Enzymes Involved:

Gyrase: Releases pressure from the DNA during the unwinding of the double helix.
Helicase: Unwinds the double helix by breaking the hydrogen bonds.
Single-Stranded binding proteins: Prevents the DNA from reforming their hydrogen bonds and twisting back into their double helical structure.
Primase: Lays down primers indicating the starting point of replication.
DNA Polymerase 3: Builds the new DNA sequence by attaching corresponding nucleotides. Builds from 5' -> 3'
DNA Polymerase 1: Removes primers and checks for incorrect DNA sequencing and corrects the mistake (s).
Ligase: Joins Oakzaki fragments with a phosphodiester bond.

1. Gyrase allows the double helix to be unwound without tension.
2. Helicase unwinds the double helix which makes an unzipped helix.
3. Single-stranded binding proteins hold the strands apart to prevent the helix from joining back together again.
4. Primase lays down primers to indicate the starting position for replication.
5. DNA polymerase 3 adds the corresponding nucleotides to the strands of DNA; they add in the direction of 5' to 3'.
The leading strand is the strand that is built continuously towards the replication fork. The lagging strand is the strand built away from the replication forks in fragments, known as Okazaki fragments.
6. DNA polymerase 1 removes the RNA primers and double checks the sequence that was made.
7. DNA ligase joins gaps between each Okazaki fragment.