The gene holds the information of how the mRNA is expressed. The gene tells what proteins and other materials the cell needs to produce. In the nucleus, the DNA unzips, breaking the bonds between the nucleotides. The RNA polymerase then binds to the promoter region of the DNA and begins to build a new complementary strand, using the rules of base pairing (A:U and C:G). This is what makes the mRNA strand, which then is transported to the cytoplasm to a ribosome, where the mRNA is then translated into protein.
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