What is the function of dna helicase? []unzip or unwind the dna []rezip or put the dna back together []put base pairs back into the dna

The main function of DNA helicase is to separate two strands of DNA for replication. DNA polymerase is the main enzyme that polymerises the DNA strands during replication. DNA replication is semiconservative, one original strand is retained and one strand is newly formed in the DNA duplex.

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explanation:

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.