Question

which of the following occurs as the ribosome shifts down the mrna by a distance of one codon? multiple choice the trna that was in the a site picks up another amino acid. the trna that was in the a site releases the growing polypeptide chain. the trna that was in the a site moves into the p site. the trna that was in the p site moves into the a site. the trna that was in the p site picks up another amino acid.

Explanation:

In the process of translation, when the ribosome shifts down the mRNA by one codon, the t - RNA that was in the A (amino - acyl) site moves into the P (peptidyl) site. The t - RNA in the A site holds a new amino - acid which is added to the growing polypeptide chain, and then it moves to the P site for the next step of elongation.

Answer:

The tRNA that was in the A site moves into the P site.