During replication, which strand is synthesized in short fragments called Okazaki fragments?

During replication, which strand is synthesized in short fragments called Okazaki fragments?

• A. Leading strand
• B. Template strand
• C. Lagging strand
• D. Both strands

Answer: (C)

During DNA replication, strands are antiparallel and DNA polymerase can only synthesize in the 5′ to 3′ direction. This means one strand, the leading strand, is copied continuously toward the replication fork. The opposite strand, the lagging strand, must be copied away from the fork in short bursts called Okazaki fragments. Each fragment starts with an RNA primer and is extended until it meets the previous fragment, then the fragments are joined by ligase. So the strand that is synthesized in short fragments is the lagging strand.

During DNA replication, strands are antiparallel and DNA polymerase can only synthesize in the 5′ to 3′ direction. This means one strand, the leading strand, is copied continuously toward the replication fork. The opposite strand, the lagging strand, must be copied away from the fork in short bursts called Okazaki fragments. Each fragment starts with an RNA primer and is extended until it meets the previous fragment, then the fragments are joined by ligase. So the strand that is synthesized in short fragments is the lagging strand.