DNA replication in bacteria like E. coli starts at a definite region known as the origin of replication (ori) . While DNA-dependent DNA polymerase synthesises the new strand only in the 5'→3' direction, the process at the replication fork involves movement in both directions away from the origin in circular bacterial chromosomes . This bi-directional movement allows for efficient duplication of the genome. Understanding these molecular mechanisms is vital for medical entrance exams, as NCERT textbooks are the primary resource for approximately 95% of NEET Biology questions .