Okazaki fragments are short DNA segments on which strand that are later joined?

Okazaki fragments are short DNA segments on which strand that are later joined?

• A. Leading strand
• B. Lagging strand
• C. Both strands
• D. RNA primer strand

Answer: (B)

During DNA replication, the two strands run antiparallel and DNA polymerase can only add nucleotides in the 5' to 3' direction. As the fork progresses, one template is read 3' to 5' toward the fork, so the new strand can be made continuously in the same direction as the fork—the leading strand. The other template runs 5' to 3' toward the fork, which means synthesis must occur in short bursts in the opposite direction. Those short bursts are Okazaki fragments, and they form on the lagging strand. After synthesis, RNA primers are removed and the fragments are joined by DNA ligase to produce a continuous strand.

During DNA replication, the two strands run antiparallel and DNA polymerase can only add nucleotides in the 5' to 3' direction. As the fork progresses, one template is read 3' to 5' toward the fork, so the new strand can be made continuously in the same direction as the fork—the leading strand. The other template runs 5' to 3' toward the fork, which means synthesis must occur in short bursts in the opposite direction. Those short bursts are Okazaki fragments, and they form on the lagging strand. After synthesis, RNA primers are removed and the fragments are joined by DNA ligase to produce a continuous strand.