Question

Transcribed regions present in mature mRNA arise from ---(i)-- and transcribed regions not present in mature mRNA arise from ----ii----.

• A. i. intron, ii. exon
• B. i. exon, ii. intron
• C. i. codon, ii. anticodon
• D. i. anticodon, ii. codon

Answer 1

The correct option is B i. exon, ii. intron

Transcribed regions present in mature mRNA arise from exons while transcribed regions not present in mature mRNA arise from introns. In eukaryotes the genes contain coding as well as non coding regions for proteins. mRNA which is produced by transcription process contains both these regions while the mature mRNA which is used for translation into protein has regions only form coding sequence. The regions in the mRNA that code for amino acids are called Exons while regions that do not code for amino acids are called Introns. The editing out of introns before an mRNA becomes a mature messenger RNA molecule is termed as post-transcriptional modification.