Final answer:
The ribosome shifts along the mRNA strand enabling the next two tRNA molecules to bind and deliver their associated amino acids, which are then attached to the growing polypeptide chain through peptide bonds.
Step-by-step explanation:
When the next two tRNA molecules are placed on the mRNA strand during the translation process, the ribosome moves to the right along the mRNA. This action brings the next codon into the correct position for the tRNA to bind via complementary base pairing. The first of these two tRNA molecules will have an anticodon that matches the second codon of the mRNA, allowing it to deliver its amino acid. The amino acid carried by this tRNA is then added to the growing polypeptide chain through a peptide bond, and the tRNA is released from the mRNA to be recycled.
The ribosome facilitates the correct bonding between the tRNA and mRNA and catalyzes the formation of the peptide bond between amino acids. As the process continues, the ribosome slides one codon along the mRNA strand, allowing the next tRNA carrying the appropriate amino acid to enter the A site and repeat the cycle of peptide chain elongation. This is a critical step in protein synthesis, ensuring that each amino acid is added in the correct sequence as dictated by the mRNA template.