Question

During DNA replication, Okazaki fragments are used to elongate:

• A. The lagging strand towards replication fork
• B. The leading strand away from replication fork
• C. The lagging strand away from the replication fork
• D. The leading strand towards replication fork

Answer 1

Answer: (C)

Two DNA polymerase molecules work simultaneous at the DNA fork, one on the leading strand and the other on the lagging strand.
Each Okazaki fragment is synthesized by DNA polymerase at lagging strand in $5^{\prime }\to 3^{\prime }$ direction. New Okazaki fragments appear as the replication fork opens further.
As the first Okazaki fragment appears away from the replication fork, the direction of elongation would be away from replication fork.