Messenger RNA (mRNA) is used during translation to form polypeptides. Describe how mRNA is produced in the nucleus of a cell.

This question, from an AQA past paper, is worth 6 marks and it is asking for you to describe the process of transcription - you do not have to explain or say why things happen. You should make 6 clear points to get the full marks on offer. You could introduce your answer by saying this process is done through transcription.
Transcription and translation can be remembered by copying and then translating into a different form (mRNA to protein.)
DNA Helicase is an enzyme which breaks hydrogen bonds between the DNA. This leaves two single strands, of which one DNA strand acts as a template. RNA nucleotides are attracted to exposed bases through complementary base pairing. Base pairing can only occur between A and U (uracil instead of thymine) and C and G. RNA polymerase joins (RNA) nucleotides together. This forms pre-mRNA. To get mRNA from this, the pre-mRNA is spliced to remove introns which are not involved in protein synthesis.