Which domain of organisms uses multiple origins of replication?

• A. Prokaryotes
• B. Eukaryotes
• C. Archaea
• D. Bacteria

Answer: (B)

Multiple origins of replication are needed to copy large, linear genomes efficiently. In eukaryotes, each linear chromosome is equipped with many replication origins, and replication forks emanate from several origins and move in both directions. This setup allows the entire genome to be replicated within the S phase timeframe despite its size. Prokaryotes, which usually have single, circular chromosomes, typically use a single origin of replication, so replication starts at one point and proceeds around the circle. While archaea (also prokaryotes) can vary, the pattern most emphasized is that eukaryotes employ multiple origins. Therefore, the domain that uses multiple origins is eukaryotes.