Which ribosomal site is responsible for releasing empty tRNAs from the ribosome?

Which ribosomal site is responsible for releasing empty tRNAs from the ribosome?

• A. A site
• B. P site
• C. X site
• D. E site

Answer: (D)

During translation, tRNA moves through three ribosomal pockets: the site that accepts charged tRNA, the site where the growing polypeptide is held, and the site where tRNA without its amino acid exits. After the peptide bond forms, the deacylated tRNA is shifted into the exit pocket and leaves the ribosome. That exit pocket is where empty tRNAs are released, allowing the ribosome to accept another charged tRNA for the next round of elongation. The entry site is for incoming charged tRNA, and the peptidyl site holds the tRNA carrying the growing chain. There isn’t a separate X site in this model.

During translation, tRNA moves through three ribosomal pockets: the site that accepts charged tRNA, the site where the growing polypeptide is held, and the site where tRNA without its amino acid exits. After the peptide bond forms, the deacylated tRNA is shifted into the exit pocket and leaves the ribosome. That exit pocket is where empty tRNAs are released, allowing the ribosome to accept another charged tRNA for the next round of elongation. The entry site is for incoming charged tRNA, and the peptidyl site holds the tRNA carrying the growing chain. There isn’t a separate X site in this model.