Question

Which best describes the process of DNA replication?

• A. Multiple "bubbles" form in the DNA that proceed with replication in both directions from the bubble.
• B. A single "bubble" forms in the DNA that proceeds with replication in a single direction from the bubble.
• C. DNA polymerase adds nucleotides to each separated strand of the DNA molecule at the replication fork replicating two leading strands at one end of the bubble and two lagging stands at the other side of the bubble.
• D. Replication occurs at a single replication fork that replicates lagging and leading strands in the same direction.

Answer 1

The correct option is A Multiple "bubbles" form in the DNA that proceed with replication in both directions from the bubble.

DNA replication in eukaryotes is multi-replicon i.e., it has many origins of replication. So multiple bubbles are formed and then fuse which results in speeding up the replication of long DNA molecule. Inside the replication bubble, the Y-shaped replication fork is formed from where the replication process starts and proceeds bidirectionally. Thus, the correct answer is option A.