Answer: Antiparallel to each other.
- A Parallel to each other
- B Antiparallel to each other
- C Perpendicular to each other
- D Randomly oriented
Correct answer: B. Antiparallel to each other
Explanation: The two polynucleotide strands of DNA run in opposite directions, one 5 prime to 3 prime and the other 3 prime to 5 prime, hence antiparallel.
Helicase unwinds the double helix at the replication fork; one new strand (leading) is synthesised continuously toward the fork, while the other (lagging) must be made in short, separate Okazaki fragments because DNA polymerase only adds nucleotides 5'→3'.
Concept context
DNA structure, replication, transcription, translation, the genetic code, and gene regulation (lac operon). The single most important chapter for NEET molecular biology.