DNA replication is the process by which DNA makes a copy of itself during cell division.
The first step in DNA replication is to ‘unzip’ the double helix structure of the DNA? molecule.
This is carried out by an enzyme?(Biological molecules, usually proteins that are responsible for thousands of metabolic processes essential to life. ) called helicase which breaks the hydrogen bonds? holding the complementary? bases? of DNA together (A with T, C with G).
The separation of the two single strands of DNA creates a ‘Y’ shape called a replication ‘fork’. The two separated strands will act as templates for making the new strands of DNA.
One of the strands is oriented in the 3’ to 5’ direction (towards the replication fork), this is the leading strand?. The other strand is oriented in the 5’ to 3’ direction (away from the replication fork), this is the lagging strand?. As a result of their different orientations, the two strands are replicated differently:
Illustration showing replication of the leading and lagging strands of DNA.