Describe how mRNA is produced in the nucleus of a cell

mRNA is a molecule produced in the process of transcription, the first stage of protein synthesis from a DNA molecule. First, DNA Helicase, an enzyme, is used to break the hydrogen bonds holding the double stranded DNA together, leaving two separate DNA strands. One strand is called the template strand and this contains bases to which free RNA nucleotides in the nucleus are attracted to. These nucleotides join up to the exposed bases on the template strand by a process called complementary base pairing. The enzyme, RNA polymerase is then used to join the RNA nucleotides to each other, forming the RNA strand, pre-mRNA. This pre-mRNA then undergoes splicing which removes introns (non-coding base sequences), resulting in the production of mRNA.