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

Question

Quizplus · Accepted Answer

DNA polymerase can join new nucleotides only to the 3' end of a preexisting strand. Thus, the leading strand, which is synthesized continuously in the direction of replication fork movement, can be continuously synthesized by DNA polymerase, whereas the lagging strand, which is synthesized discontinuously in the opposite direction of fork movement, requires repeated initiation by primase and synthesis of short Okazaki fragments that are later joined by DNA ligase.

What Is the Basis for the Difference in How the Leading