sentences:  This transition involves the ordered assembly of additional replication factors to unwind the DNA and accumulate the multiple eukaryotic DNA polymerases around the unwound DNA.Central to the question of how bidirectional replication forks are established at replication origins is the mechanism by which ORC recruits two head-to-head Mcm2-7 complexes to every replication origin to form the pre-replication complex.The first step in the assembly of the pre-replication complex (pre-RC) is the binding of the origin recognition complex (ORC) to the replication origin.