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DNA Replication
Also known as the semi-conservative replication, it is the process of making an identical copy of a DNA molecule to pass the genetic trait,
The new DNA has one parent strand and one daughter strand.
DNA elongates and slants in the 5’ to 3’ manner only.
DNA Replication as Semi-discontinuous
The leading strand is synthesized continuously (5’ to 3’).
The lagging strand is produced discontinuously in short stretches called Okazaki fragments.
Process of DNA Replication
The parental molecule has two complementary strands of DNA. Each base is paired by hydrogen bonding.
The two DNA strands are separated by the helicase enzyme to form a replication fork. Each strand is a template for a new complementary strand.
Single-strand binding proteins prevent the unwound strands from rejoining.
Topoisomerase untwists the double helix.
Primase makes a short stretch of RNA on the DNA template, called a primer
DNA Polymerase will add nucleotides complementary to the bases of the parental strand to form the new backbone of the strand. This replaces the RNA primer
The leading strand synthesizes continuously.
The lagging strand will synthesize discontinuously.
Exonuclease removes the RNA primer as the DNA Polymerase replaces it with the DNA strand
Ligase seals the sugar phosphate backbone, forming the phosphodiester bonds.
Helicase
an enzyme that separate the strands using hydrogen bonds
Single-strand binding proteins
They prevent the unwound strands from rejoining with one another.
Topoisomerase
it untwists the double helix
Primase
makes a short RNA primers on the DNA template to serve as guides as nucleotides will only attach to an existing strands
DNA Polymerase
adds DNA nucleotides to the RNA primer; only adds from the 5’ end to the 3’ end
Ligase
seals the sugar-phosphate backbone
Exonuclease
removes the RNA primer
Synthesis of Lagging Strand
Primase and DNA Polymerase take turns creating the RNA primer for one strand and creating the new DNA for it
Note 
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