Final answer:
The correct answer is D) tmRNA, which rescues stalled ribosomes by acting as both tRNA and mRNA, allowing for the release and degradation of the problematic polypeptide and the ribosome to resume translation.
Step-by-step explanation:
The molecule that allows the release of mRNA from a stalled ribosome is D) tmRNA. tmRNA has a unique role in bacterial cells; it acts as both tRNA and mRNA, and it's used by ribosomes to free themselves when stuck during translation. It does this by adding an alanine residue to the polypeptide being synthesized and then providing a short template for the ribosome to add a few more amino acids. This action signals to the cell that the problematic polypeptide needs to be degraded, and the ribosome is released to begin the process of translation again.
Roles of RNA in Translation
- B. the small ribosomal subunit and C. the large ribosomal subunit are both essential to the ribosome's function in translation.
D. the initiator tRNA is charged with the first amino acid methionine and starts the process of translation by binding to the start codon on the mRNA.
During elongation in translation, an incoming charged tRNA molecule binds to the A site of the ribosome.
The rRNA is the component of the ribosome with catalytic abilities, as suggested in question 13. When the ribosome reaches a nonsense codon, the polypeptide is released, as indicated by the option B in question 15.
Other RNA-related functions are: mRNA, the messenger molecule that provides the code for protein synthesis; rRNA is a critical component of the ribosome that has structural and catalytic roles; and tRNA, which transfers specific amino acids to the growing polypeptide chain during translation.