[Campbell Biology P.427] Which of the following is a described mechanism for regulating the ... | Practice Question

Which of the following is a described mechanism for regulating the initiation of translation in eukaryotic cells, according to the text?

  • A: Regulatory proteins binding to the coding region of mRNA to block ribosome attachment.
  • B: Activation or inactivation of protein factors required for translation initiation.
  • C: Degradation of the 5' cap and poly-A tail to enhance ribosome binding.
  • D: Removing introns from the mRNA prior to translation.

Explanation

The text describes two main ways translation is regulated: by regulatory proteins binding to the untranslated regions UTRs of mRNA, preventing ribosome attachment, and by 'global' control involving the activation or inactivation of protein factors necessary for translation initiation. Option B directly reflects this 'global' control mechanism. Options A, C, and D describe incorrect or irrelevant processes regarding the initiation of translation. Regulatory proteins bind to UTRs, not coding regions. Degradation of the cap and tail would inhibit, not enhance, ribosome binding. Intron removal is splicing, a precursor to translation, not a direct initiation regulation.