Which component is the last to join the initiation complex during the initiation of translation?

the mRNA molecule

the small ribosomal subunit

the large ribosomal subunit

the initiator tRNA

The correct answer is the third option - the large ribosomal unit.

Explanation:

The translation is the second process of the protein synthesis in which transcribed mRNA molecule and transfer RNA or tRNA and ribosomes assemble together and complete synthesis of peptide chain or protein.

The assembly of initiator tRNA to ribosome subunits at the start codon of the mRNA is the initiation complex of the translation. The initiator tRNA is basically a met-tRNA molecule.

The initiator tRNA is bound to small subunit (30S) at 5' cap and scan for the start codon of mRNA.

Start codon bind to initiator RNA and in the end larger ribosomal unit assemble to this complex to complete the initiation complex of translation.

Thus, the correct answer is option - the large ribosomal subunit