How does the antiparallel nature of the DNA molecule affect its replication?

• A. It enables the replication fork to move in both directions simultaneously.
• B. It requires the leading strand to be synthesized continuously and the lagging strand discontinuously.
• C. It allows DNA polymerase to synthesize both strands simultaneously in the same direction.
• D. It prevents the formation of Okazaki fragments during replication.

Answer: (B)

Verified step by step guidance

1. Understand the structure of DNA: DNA is composed of two strands that run in opposite directions, known as antiparallel. One strand runs in the 5' to 3' direction, while the other runs in the 3' to 5' direction.
2. Recognize the role of DNA polymerase: DNA polymerase is the enzyme responsible for synthesizing new DNA strands. It can only add nucleotides to the 3' end of a growing DNA strand, meaning it synthesizes in the 5' to 3' direction.
3. Identify the leading and lagging strands: During replication, the leading strand is synthesized continuously in the direction of the replication fork movement, as it is oriented in the 5' to 3' direction.
4. Understand the synthesis of the lagging strand: The lagging strand is oriented in the 3' to 5' direction, which requires it to be synthesized discontinuously in short segments called Okazaki fragments, which are later joined together.
5. Conclude the effect of antiparallel nature: The antiparallel nature of DNA necessitates the continuous synthesis of the leading strand and the discontinuous synthesis of the lagging strand, resulting in the formation of Okazaki fragments.