A transfer RNA (#1) attached to the amino acid lysine enters the ribosome. The lysine binds to the growing polypeptide on the other tRNA (#2) in the ribosome already. Where does tRNA #2 move to after this bonding of lysine to the polypeptide?

Options for the question have not been give. They are as follows:

A. P site

B. A site

C. E site

D. directly to the cytosol

E. exit tunnel

C. E site

Explanation:

Translation is the process by which mRNA is converted into polypeptide chain. Translation machinery has three binding slots for tRNA : A, P and E. Any incoming tRNA encounters A, P and E site in that order.

When a new tRNA (#1) carrying the next amino acid (here, lysine) comes, it enters the A site. Peptide bond is formed between lysine and the already existing amino acid on the growing polypeptide chain on the preceding tRNA (#2). Once lysine is added to the polypeptide chain, the entire chain moves to tRNA #1 which makes tRNA #2 empty. Meanwhile, the machinery moves forward. As a result, tRNA #1 slides to P site and tRNA #2 slides to E site. The A site is empty now and can receive another tRNA.

answer; i believe the correct answer is (replication is not conservative);