Which enzyme unwinds the DNA double helix to enable replication?

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Multiple Choice

Which enzyme unwinds the DNA double helix to enable replication?

Explanation:
Unwinding the DNA double helix is the essential first step to replication. This job is done by DNA helicase, an enzyme that uses energy from ATP to break the hydrogen bonds between base pairs, opening the double helix and creating a replication fork so each strand can serve as a template. Once the strands are separated, DNA polymerases can synthesize new DNA by adding nucleotides in the 5' to 3' direction. The primer is supplied by primase to provide a starting point for synthesis, but primase itself does not unwind DNA. Ligase then seals the gaps after synthesis, joining Okazaki fragments on the lagging strand. So the enzyme responsible for unwinding the helix to enable replication is DNA helicase.

Unwinding the DNA double helix is the essential first step to replication. This job is done by DNA helicase, an enzyme that uses energy from ATP to break the hydrogen bonds between base pairs, opening the double helix and creating a replication fork so each strand can serve as a template. Once the strands are separated, DNA polymerases can synthesize new DNA by adding nucleotides in the 5' to 3' direction. The primer is supplied by primase to provide a starting point for synthesis, but primase itself does not unwind DNA. Ligase then seals the gaps after synthesis, joining Okazaki fragments on the lagging strand. So the enzyme responsible for unwinding the helix to enable replication is DNA helicase.

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