Each eukaryotic mRNA, even after post-transcriptional modification, includes 5' and 3' UTRs. Which are these?
A)the cap and tail at each end of the mRNA
B)the untranslated regions at either end of the coding sequence
C)the U attachment sites for the tRNAs
D)the U translation sites that signal the beginning of translation
E)the U - A pairs that are found in high frequency at the ends

Question

Quizplus · Accepted Answer

UTRs stand for "untranslated regions," and refer to the non-coding segments of an mRNA molecule that precede (5' UTR) or follow (3' UTR) the coding sequence. These regions are involved in regulation of gene expression and other processes, but do not directly code for protein. The cap and tail (A) are structures added to the ends of the mRNA during processing, while the U attachment sites for tRNA (C) and U translation sites (D) are not part of the mRNA molecule itself. U-A pairs (E) are not specific to UTRs and do not serve a particular function in this context.

Each Eukaryotic MRNA, Even After Post-Transcriptional Modification, Includes 5' and 3