transcription

• Transcription is the process of copying a segment of DNA into RNA
• In transcription RNA polymerase moves along the DNA unwinding the strand
• In transcription, a complimentary copy of the code from the gene is made by building a single-stranded nucleic acid molecule known as mRNA (messenger RNA)
• Transcription occurs in the nucleus while translation takes place in the cytoplasm
• In transcription, free RNA nucleotides pair up (via hydrogen bonds) with their complementary (now exposed) bases on the template strand
• In transcription, RNA polymerase forms phosphodiester bonds between the sugar-phosphate groups of the RNA nucleotides, which makes the sugar-phosphate backbone of the mRNA molecule
• When the gene has been fully transcribed, the hydrogen bonds between the mRNA and DNA strands break and the double-stranded DNA molecule re-forms
• After transcription, the mRNA molecule leaves the nucleus via a pore in the nuclear envelope