[Campbell Biology P.399] Which of the following accurately describes the function of the rib... | Practice Question

Which of the following accurately describes the function of the ribosome's tRNA binding sites during translation?

  • A: The A site holds the tRNA carrying the growing polypeptide chain.
  • B: Discharged tRNAs exit the ribosome from the P site.
  • C: The E site is where the tRNA carrying the next amino acid enters the ribosome.
  • D: The P site holds the tRNA attached to the growing polypeptide, and the A site holds the tRNA with the next amino acid to be added.

Explanation

The text explicitly defines the roles of the three tRNA binding sites: 'The P site peptidyl-tRNA binding site holds the tRNA carrying the growing polypeptide chain, while the A site aminoacyl-tRNA binding site holds the tRNA carrying the next amino acid to be added to the chain. Discharged tRNAs leave the ribosome from the E site exit site .'