Question

Translation is terminated when a stop codon is presented at the

a)A site.
b)P site.
c)E site.
d)either the A or P site.
e)either the A or E site.

Answer 1

Translation ends when a stop codon (UAA, UAG, or UGA) reaches the A site of the ribosome, triggering the release of the protein and the dissociation of the ribosomal subunits.

Step-by-step explanation:

Translation is terminated when a stop codon is presented at the A site of a ribosome. The stop codons (UAA, UAG, or UGA) do not code for an amino acid but are rather signals for termination.

When a stop codon arrives at the A site, it is recognized by a release factor, which then instructs peptidyl transferase to add a water molecule to the carboxyl end of the P-site amino acid. This triggers the release of the newly synthesized protein and the subsequent dissociation of the ribosomal subunits.