Question

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

1) The large ribosomal subunit binds to the small ribosomal subunit.
2) The small ribosomal subunit binds to an mRNA sequence near the 5' end of the transcript
3) The large ribosomal subunit binds to an mRNA sequence near the 5' end of the transcript
4) The small ribosomal subunit binds to an mRNA sequence near the 3' end of the transcript.

Answer 1

The initial step of forming the translation initiation complex is the binding of the small ribosomal subunit to the mRNA near the 5' end, followed by the identification of the start codon AUG. so, option 2 is the correct answer.

Step-by-step explanation:

The first step in the formation of the translation initiation complex is when the small ribosomal subunit binds to an mRNA sequence near the 5' end of the transcript. This process involves initiation factors that help the small subunit to bind and scan the mRNA until it identifies the AUG start codon. Once the start codon is recognized, the initiator tRNA with its anticodon hydrogen bonds to the start codon. Following this, the large ribosomal subunit binds to this initiation complex, completing the initiation phase of translation.

The first step in the formation of the translation initiation complex is when the small ribosomal subunit binds to an mRNA sequence near the 5' end of the transcript.