Once the DNA has been unzipped, what puts the complimentary RNA nucleotides into place

RNA polymerase

Explanation:

This question describes the process of transcription, which is the first stage of gene expression involving the formation of a RNA molecule from a DNA template. In the process of transcription, an enzyme called RNA polymerase binds to a region on the DNA called PROMOTER region. The double-helical structure of the DNA molecule is then unzipped allowing RNA polymerase to synthesize RNA nucleotides using the nucleotides it reads from the DNA.

The RNA polymerase synthesizes RNA nucleotides on the RNA molecule using complementary base pairing i.e. it synthesizes Uracil nucleotide for every Adenine nucleotide it reads on the DNA while it synthesizes Cytosine for every Guanine it reads on the DNA and vice versa (A-U, G-C).

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