Steps for DNA replication?

In the process of DNA replication, the DNA makes multiple copies of itself. It is a biological polymerization which proceeds in the sequence of initiation, elongation, and termination. The whole process takes place with the help of enzymes where DNA-dependent DNA polymerase being the chief enzyme.

Following are the important steps involved in DNA replication:

Initiation

DNA replication demands a high degree of accuracy because even a minute mistake would result in mutations. Thus, replication cannot initiate randomly at any point in DNA.

For the replication to begin there is a particular region called the origin of replication. This is the point where the replication originates. Replication begins with the spotting of this origin followed by the unwinding of the two DNA strands.

Unzipping of DNA strands in its entire length is unfeasible due to high energy input. Hence, first, a replication fork is created catalyzed by polymerases enzyme which is an opening in the DNA strand.

Elongation

As the strands are separated, the polymerase enzymes start synthesizing the complementary sequence in each of the strands. The parental strands will act as a template for newly synthesizing daughter strands.

It is to be noted that elongation is unidirectional i.e. DNA is always polymerized only in the 5′ to 3′ direction.  Therefore, in one strand (the template 3‘→5‘) it is continuous, hence called continuous replication while on the other strand (the template 5‘→3‘) it is discontinuous replication. They occur as fragments called Okazaki fragments. The enzyme called DNA ligase joins them later.