Describe the process and purpose of transcription
The purpose of transcription is to produce an mRNA copy of a gene, to allow the genetic information to pass out of the nucleus, through the nuclear pores where it can be used to assemble a protein.
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Enzyme DNA helicase uncoils a region of the DNA double-helix by breaking the hydrogen bonds between the base pairs.
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Complementary nucleotides from the nucleoplasm align up to the exposed base pairs on the template DNA strands
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The enzyme RNA polymerase moves along the strand, joining adjacent nucleotides together by phosphodiester bonds.
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This process continues until RNA polymerase reaches a stop codon and the production of pre-mRNA is complete.
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Non-coding introns are then spliced out by enzymes in the spliceosome and the mRNA strand leaves the nucleus.
