DNA History, Replication, and Protein Synthesis Practice Test

Origins of replication determine where DNA synthesis begins. In prokaryotes with a circular chromosome, replication starts at a single origin and proceeds bidirectionally until the entire genome is copied. In contrast, eukaryotic chromosomes are long and linear, so many origins fire during S phase, creating multiple replication forks that collectively copy the whole chromosome efficiently.

This is why the statement about prokaryotes having a single origin per chromosome and eukaryotes having multiple origins per chromosome is the best description. The other ideas don’t fit because prokaryotes generally don’t use multiple origins, eukaryotes don’t rely on a single origin per chromosome, origins aren’t per gene, and replication isn’t restricted to telomeres alone in eukaryotes.