Question

Why does the lagging strand run into trouble when replicating?

A) Limited supply of DNA polymerase
B) Replication fork moves too fast
C) DNA ligase is too efficient
D) High concentration of adenine

Answer 1

Trouble with lagging strand replication stems from the DNA polymerase's limitation to only synthesize DNA in the 5' to 3' direction, leading to a discontinuous replication process in the form of short Okazaki fragments.

Step-by-step explanation:

The lagging strand runs into trouble during DNA replication because DNA polymerase can only extend in the 5' to 3' direction. This poses a problem since the DNA double helix is anti-parallel. As a result, the lagging strand, which is complementary to the 5' to 3' parental DNA strand, must be extended away from the replication fork in short stretches known as Okazaki fragments. Each of these fragments requires a primer to start the synthesis, making the process discontinuous and more complex compared to the leading strand replication, which occurs in a continuous fashion.