What is the basis for the difference in how the leading and lagging strands of DNA molecules are synthesized?
A) The origins of replication occur only at the 5' end.
B) Helicases and single-strand binding proteins work at the 5' end.
C) DNA polymerase can join new nucleotides only to the 3' end of a growing strand.
D) DNA ligase works only in the 3' → 5' direction.
E) Polymerase can work on only one strand at a time.

Question

Quizplus · Accepted Answer

DNA polymerase can only add nucleotides to the 3' end of a growing strand, meaning that the leading strand can be synthesized continuously in the 5' to 3' direction, while the lagging strand must be synthesized in short, discontinuous fragments called Okazaki fragments that are ultimately joined by DNA ligase.

Answer: A, B, D, and E are incorrect.
 None of the other choices accurately describe the differences between leading and lagging strand synthesis.

What Is the Basis for the Difference in How the Leading