During DNA replication, which enzyme is responsible for synthesizing new DNA strands?

The enzyme responsible for synthesizing new DNA strands during DNA replication is DNA polymerase. This enzyme plays a crucial role in the replication process by adding nucleotides to the growing DNA strand, using the original template strand as a guide. DNA polymerase ensures that the new DNA strands are complementary to the template strands, helping to maintain genetic fidelity.

Furthermore, DNA polymerase has a proofreading ability, which allows it to correct any mistakes made during replication, further enhancing the accuracy of the process. This capability is essential in preventing mutations that could lead to disorders or diseases.

The other enzymes listed do not play a direct role in synthesizing new DNA strands. For example, RNA polymerase is involved in synthesizing RNA from a DNA template, DNA ligase is responsible for joining Okazaki fragments and sealing nicks in the DNA backbone after replication, and helicase unwinds the double-stranded DNA to allow access for replication but does not synthesize the DNA itself. Thus, DNA polymerase is the key enzyme in the synthesis of new DNA during replication.