Question

what is the purpose of dna helicase?
destroying the initial dna strand once its not needed anymore
\unzipping\ the original dna strand before replication begins
adding base pairs to the new strand during replication

Explanation:

To determine the purpose of DNA helicase, we analyze each option:

• The first option is incorrect because DNA helicase does not destroy DNA strands.
• The second option is correct. DNA helicase functions to break the hydrogen bonds between the base pairs of the double - stranded DNA, which is like "unzipping" the original DNA strand so that DNA replication can start.
• The third option is incorrect. The enzyme that adds base pairs to the new strand during replication is DNA polymerase, not DNA helicase.

Answer:

B. "unzipping" the original DNA strand before replication begins