Which one of the following structures, if missing, would usually prevent translation from starting?
A) exon
B) 5′ cap
C) AUG codon
D) poly-A tail

Question

Quizplus · Accepted Answer

The AUG codon is the start codon that signals the beginning of translation. If it is missing or altered, translation will not be able to start.

All other answer choices are important for efficient translation but are not essential for translation initiation. Exons are coding sequences within a gene, the 5′ cap is a modification on the 5′ end of mRNA that enhances stability and assists in ribosome binding, and the poly-A tail is a stretch of adenine nucleotides added to the 3′ end of mRNA that also enhances stability. However, the absence of any of these structures would not necessarily prevent translation from starting.

Which One of the Following Structures, If Missing, Would Usually