transcription Flashcards
where does transcription occur?
nucleus
what is the first step of transcription?
enzyme breaks hydrogen bonds between the DNA nucleotides
what is the second step of transcription?
part of the gene is unzipped and the two strands separate
what is the third step of transcription?
free RNA nucleotides bind to the exposed bases on the template strand using hydrogen bonds
what is the fourth step of transcription?
RNA polymerase attaches to the promoter region of the template strand
it moves along the template strand, in the 3’ to 5’ direction joining the RNA nucleotides in a condensation reaction forming phosphodisester bonds
what is the fifth step of transcription?
the new mRNA strand is synthesised in the 5’ to 3’ direction
what is the sixth step of transcription?
once part of the mRNA strand is synthesised, the next section of the gene unzips and the process is repeated
what is the seventh step of transcription?
once RNA polymerase reaches the end of the gene, the STOP triplet, it dissociates from the template strand and releases mRNA
what is the relationship between the DNA coding strand and the mRNA codons?
they are copies of each other with the T replaced by the U
