The following is a portion of an mRNA sequence 3AUCGUCAUGCAG

The following is a portion of an mRNA sequence: 3\'-AUCGUCAUGCAGA-5\' During transcription, was the adenine at the left-hand side of the sequence the first or the last nucleotide added to the portion of mRNA shown?

Solution

The last because that is the way you read a strand of DNA, in the 5\' to 3\' direction.

The synthesis of a strand of DNA is in the 5’ to 3’ direction