The first step in replication is to break the hydrogen bonds between the bases. This is accomplished by the enzyme ______.

The first step in replication is to break the hydrogen bonds between the bases. This is accomplished by the enzyme ______.

• A. DNA Polymerase
• B. Helicase
• C. Ligase
• D. Primase

Answer: (B)

Unwinding the double helix to expose the templates is the first move in replication. This is accomplished by helicase, an enzyme that uses energy from ATP to break the hydrogen bonds between the base pairs, separating the two strands and forming the replication fork. Once the strands are separated, other enzymes take over to synthesize new DNA: primase lays down an RNA primer to provide a starting point for DNA polymerase, DNA polymerase builds the new strands, and ligase seals the completed fragments.

Unwinding the double helix to expose the templates is the first move in replication. This is accomplished by helicase, an enzyme that uses energy from ATP to break the hydrogen bonds between the base pairs, separating the two strands and forming the replication fork. Once the strands are separated, other enzymes take over to synthesize new DNA: primase lays down an RNA primer to provide a starting point for DNA polymerase, DNA polymerase builds the new strands, and ligase seals the completed fragments.