During DNA replication, why is it that the entire molecule does not open in one go? Explain replication fork. What are the two functions that the monomers (d NTPs) play?

During DNA replication, why is it that the entire molecule does not open in one go otherwise the whole molecule would destabilise as it consumes a lot of energy.

2.This is because the opening or unwinding of the DNA creates tension in the molecule. Uncoiled parts start forming supercoils due to the interaction of the exposed nucleotides.

3.To avoid this scenario the helicase enzyme acts on the site of origin (ori site) of the double stranded DNA and opens only a small stretch.

4.With the help of enzymes these exposed strands are copied.

5.After this the site of origin moves in both the directions forming a ‘Y’ shaped structure called Replication Fork.

DNTP’S are Deoxyribonucleotide triphosphate. The two functions that the monomers (d NTPs) play are:

1. They provide energy for polymerisation reaction.

2. They provide deoxyribonucleotides for DNA replication.