In what direction does DNA elongation occur during replication?

During DNA replication, the elongation of the new DNA strand occurs in the 5' to 3' direction. This is due to the mechanism by which DNA polymerase, the enzyme responsible for synthesizing new DNA strands, functions. DNA polymerase can only add nucleotides to the 3' end of a growing DNA chain. Therefore, as it adds complementary nucleotides to the template strand, the new strand is built in a direction that progresses from the 5' end towards the 3' end.

In addition, the antiparallel nature of DNA strands—as one strand runs in the 5' to 3' direction, the complementary strand runs in the opposite direction (3' to 5')—enables the replication process to occur efficiently. This directional growth is fundamental in maintaining the fidelity of DNA replication, as well as in the overall mechanism of copying genetic material during cell division.

The other choices reflect incorrect understandings of DNA strand synthesis. For example, 3' to 5' would suggest the addition of nucleotides in a direction contrary to the natural synthesis by DNA polymerase. Options 5' to 2' and 3' to 2' do not represent any standard