DNA replication
DNA replication or DNA synthesis is the process of copying a double-stranded DNA molecule
As each DNA strand holds the same genetic information, both strands can serve as templates for the reproduction of the opposite strand. The template strand is preserved in its entirety and the new strand is assembled from nucleotides. The resulting double-stranded DNA molecules are identical
In a cell, DNA replication must happen before cell division.
DNA replication may also be performed in the laboratory in a process known as PCR.
Steps in DNA Replication
First , the DNA unwinds and the hydrogen bonds between the two strands are broken . This process is aided by the enzyme helicase
Single – strand binding protiens ( SSBs ) keep the strands from joining together . This creates a replication bubble
Replication bubbles form at multiple sites along the DNA molecule , greatly speeding up replication
Once the strands have been unwound and separated , DNA polymerase can begin to build a new strand
DNA polymerase reads the parent strand in a 3 to 5 direction while building the new strand in the opposite ( 5 to 3 ) direction
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