Question

Select ALL of the following events that occur during the initiation step of translation:

(Keep in mind that some of these will describe transcription initiation instead of
translation initiation.)
1. RNA polymerase reaches a promoter.
2. RNA polymerase reaches a start codon.
3. Ribosome subunits come together.
4. A ribosome binds to mRNA at the a start codon.
5. A ribosome binds at the following set of three bases in mRNA: UAA
6. A molecule carrying methionine arrives at the ribosome

Answer 1

During the initiation step of translation, (3). ribosome subunits come together, (4). a ribosome binds to mRNA at the start codon, and (5). a molecule carrying methionine (initiator tRNA) arrives at the ribosome.

Step-by-step explanation:

In the initiation step of translation, several events occur that mark the beginning of protein synthesis. The events that belong to the initiation phase of translation are:

• Ribosome subunits come together.

• A ribosome binds to mRNA at the start codon (AUG).

• A molecule carrying methionine arrives at the ribosome, which is the initiator tRNA with methionine, the first amino acid in the newly forming polypeptide chain.

Therefore, statements 3, 4, and 6 describe events that occur during the initiation step of translation. Statements 1 and 2 pertain to transcription initiation, not translation, and statement 5 describes a stop codon, which is involved in termination, not initiation of translation.