[Campbell Biology P.428] Which of the following statements accurately describes the stabilit... | Practice Question

Which of the following statements accurately describes the stability and regulation of mRNA molecules?

  • A: Bacterial mRNA molecules generally have a longer lifespan compared to eukaryotic mRNA, allowing for slower adaptation to environmental changes.
  • B: The 3' untranslated region (UTR) of an mRNA molecule has no impact on its stability or degradation rate.
  • C: Eukaryotic mRNA molecules, such as those for hemoglobin, can be exceptionally stable and translated repeatedly, contributing to prolonged protein synthesis.
  • D: The degradation of mRNA molecules is exclusively controlled by the cell's ribosomes, which directly break down unwanted transcripts.

Explanation

The text states that eukaryotic mRNA molecules, such as those for hemoglobin, can be 'unusually stable, and these long-lived mRNAs are translated repeatedly in red blood cells.' This directly supports option C. Options A and B are incorrect as bacterial mRNA has a short lifespan and the 3' UTR is crucial for stability. Option D is incorrect as mRNA degradation involves various mechanisms beyond just ribosomes.