Question

the following model represents the elongation stage of protein translation.
which arrow represents a trna leaving the ribosome after transferring an amino acid to a growing polypeptide chain?
choose 1 answer:
a arrow 1
b arrow 2
c arrow 3
d arrow 4

Explanation:

In the elongation stage of protein translation, tRNA brings amino acids to the ribosome. After transferring its amino acid to the growing polypeptide chain, the tRNA without the amino acid (the deacylated tRNA) exits the ribosome from the E - site (exit site). Looking at the model:

• Arrow 1: Seems to be a tRNA entering or positioning, not exiting after transfer.
• Arrow 2: Likely involved in peptide bond formation or amino acid addition, not exiting.
• Arrow 3: Represents the tRNA that has already transferred its amino acid and is leaving the ribosome (from the E - site).
• Arrow 4: Is a new tRNA bringing an amino acid, not exiting after transfer.

Answer:

C. Arrow 3