What enzyme is essential for DNA replication?

DNA polymerase is the key enzyme in DNA replication, playing a crucial role in synthesizing new strands of DNA during the replication process. It catalyzes the addition of nucleotide triphosphates to the growing DNA chain, creating a complementary strand to the template DNA. This enzyme ensures that the new strand is accurately formed based on the sequence of the template strand, which is vital for maintaining genetic fidelity during cell division.

In addition to synthesizing DNA, DNA polymerase also has proofreading abilities that help correct any mispaired nucleotides, thus minimizing errors in the replicating DNA. This error-checking mechanism is essential for preserving the integrity of the genetic information passed on to daughter cells.

While other enzymes mentioned in the choices play important roles in DNA metabolism—such as helicase, which unwinds the double helix to provide single strands for replication and RNA polymerase, which synthesizes RNA from a DNA template—the primary function of DNA polymerase is the actual synthesis of new DNA strands. ATP synthase is involved in ATP production and not directly in DNA replication. Hence, DNA polymerase stands out as the essential enzyme directly responsible for the replication process.