Question

Which of the following best describes the first step in the formation of the translation initiation complex?

A. Binding of mRNA to the small ribosomal subunit
B. Association of initiator tRNA with the small ribosomal subunit
C. Recognition of the start codon by the large ribosomal subunit
D. Formation of the peptide bond between the initiator tRNA and the amino acid

Answer 1

The first step in the formation of the translation initiation complex is binding of mRNA to the small ribosomal subunit. Initiation factors help the small subunit bind and scan along until it identifies the AUG start codon.

Step-by-step explanation:

The first step in the formation of the translation initiation complex is binding of mRNA to the small ribosomal subunit. Initiation factors help the small subunit bind and scan along until it identifies the AUG start codon.

Next, the anticodon of the initiator tRNA hydrogen bonds to the start codon.

Finally, the large subunit of the ribosome binds, lining up so the initiator tRNA is in the P site. This step completes initiation of translation.