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5. What is the function of a stop codon?

• tells ribosomes and tRNA molecules to attach to a strand of mRNA and begin reading and translating the codons that follow
tells ribosomes and tRNA to package the proteins for transport out of the cell
• tells ribosomes and tRNA to return to the nucleus of the cell
• tells ribosomes and tRNA to stop reading codons and detach

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Answer:

It ends protein synthesis. It also helps to detach the peptide chain from the tRNA

Step-by-step explanation:

The growing peptide chain gets transferred over and over from one tRNA to the next (based on the codon sequence). This reaction is called an aminoacyl, and it is the reaction that is catalyzed by the ribosomal RNA.

The stop codon termination factor doesn't have an amino acid on it, so when the aminoacyl transfer reaction takes place to move the peptide chain off the tRNA and onto the "next" tRNA (Termination factor), the peptide chain gets 'dropped', and the peptide is now free of the ribosome and is able to fold up into the functional protein.

This is a simplified version of the process, but the aminoacyl transfer reaction is a very important part of the stop codon process.

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