When DNA replicates, each strand of the original DNA molecule is used as a template for the synthesis of a second, complementary strand. Compare and contrast the replication of the two new strands, listing and explaining at least one similarity and one difference in the methods of synthesis.
See the answer below
A typical double-stranded DNA consists of a leading and a lagging strand with 5′ to 3′ direction and 3′ to 5′ direction respectively. During replication, a RNA primer binds to each strand at the replication origin and DNA polymerase enzyme adds complementary nucleotides to the primer to elongate the new strand until the end of each strand is reached.
The replication process of the two strands are similar such that:
- Both require RNA primer binding
- Both require DNA polymerase to add nucleotides in 5′ to 3′ direction
The replication of the two strands are different in a certain way:
- The enzyme responsible for adding nucleotide bases to the growing DNA strand during replication can only add in 5′ to 3′ direction. Consequently, the leading strand is synthesized in a continuous manner while the lagging strand is synthesized discontinuously in short nucleotide sequences known as the Okazaki fragments. The fragments are later joined together by an enzyme known as DNA ligase.
- This means that the RNA primer only binds at a single location on the leading strand while multiple primers bind at multiple locations on the lagging strand. The replication of the two