how is a dna molecule constructed quizlet
Transcription: 1. The DNA unzips like it did during DNA replication. One strand of DNA is transcribed or copied to make a messenger RNA (mRNA) molecule.The nitrogenous bases pair up. Uracil is now paired up with adenine for RNA. 2. Once the mRNA has transcribed the message, it breaks away from the DNA strand.ranscription: 1. The DNA unzips like it did during DNA replication. One strand of DNA is transcribed or copied to make a messenger RNA (mRNA) molecule.