The DNA Replication Fork

In the cell, DNA replication always initiates at specific locations on the DNA called the origin of replication.

At the start of replication, the enzyme DNA helicase binds and moves along the DNA strand, unwinding and separating the DNA. 

The resulting Y-shaped structure formed by the separate strands of DNA looks like a two-tined fork and becomes a site of DNA replication; therefore, this structure is known as the “Replication Fork”.

These separate, single-stranded DNA molecules are prone to form double-stranded hairpin loops or to rewind with the other strand. 

To prevent this from happening, single-strand DNA binding proteins, or SSBs, bind to single-stranded DNA and inhibit rewinding.

Now the exposed single strands of DNA can act as templates for the synthesis of the complementary daughter strands.