Question

During replication, which strand of the new DNA is synthesized from the 5' to 3' strand of original DNA?

A) beginning strand
B) ending strand
C) leading strand
D) lagging strand
E) trailing strand

Answer 1

The new DNA strand synthesized from the 5' to 3' strand of original DNA during replication is the leading strand, which is made continuously toward the replication fork.

Step-by-step explanation:

During DNA replication, the strand of new DNA that is synthesized from the 5' to 3' strand of the original DNA is known as the leading strand. The DNA polymerase enzyme is only able to add nucleotides in the 5' to 3' direction, so the leading strand is synthesized continuously in the direction toward the replication fork. In contrast, the opposite strand, called the lagging strand, is synthesized discontinuously in the direction away from the replication fork, in short segments known as Okazaki fragments. Each of these fragments requires a primer to start synthesis.