Question 1

Which of the following statements best describes the directionality of translation in cells?

Accepted Answer

mRNA is read from 5' to 3', and the polypeptide is synthesized from the N-terminus to the C-terminus.

Question 2

A mutation changes the codon UAU to UAA in an mRNA sequence. What is the most likely consequence of this mutation during translation?

Accepted Answer

The ribosome will terminate translation at this codon, producing a truncated protein.

Question 3

Which of the following best explains why the genetic code is described as 'degenerate'?

Accepted Answer

Some amino acids are specified by more than one codon.

Question 4

What is the role of aminoacyl-tRNA synthetase in translation?

Accepted Answer

It attaches the correct amino acid to its corresponding tRNA.

Question 5

Which of the following antibiotics inhibits the binding of aminoacyl-tRNA to the 30S ribosomal subunit in bacteria?

Accepted Answer

Tetracycline

Question 6

A tRNA with the anticodon 3'-UAC-5' will base pair with which mRNA codon?

Accepted Answer

5'-AUG-3'

Question 7

Which of the following is true about the 'wobble' position in codon-anticodon pairing?

Accepted Answer

Wobble allows a single tRNA to recognize multiple codons for the same amino acid.

Question 8

In prokaryotes, what sequence helps the ribosome identify the correct start codon for translation initiation?

Accepted Answer

Shine-Dalgarno sequence

Question 9

Which of the following best describes the function of the P site in the ribosome during translation?

Accepted Answer

It holds the tRNA carrying the growing polypeptide chain.

Question 10

Which of the following codons is the most common start codon in both prokaryotes and eukaryotes?

Accepted Answer

AUG

Question 11

A researcher adds puromycin to a bacterial translation reaction. What is the most likely outcome?

Accepted Answer

Translation will terminate prematurely due to puromycin acting as an aminoacyl-tRNA analog.

Question 12

Which of the following best explains why mitochondria have a slightly different genetic code than the universal code?

Accepted Answer

Mitochondria evolved from bacteria and retained some unique codon assignments.

Question 13

Which of the following is a direct result of the non-overlapping nature of the genetic code?

Accepted Answer

A single nucleotide change affects only one codon.

Question 14

Which elongation factor is responsible for delivering aminoacyl-tRNA to the A site of the ribosome in bacteria?

Accepted Answer

EF-Tu

Question 15

A mutation in the gene encoding the Shine-Dalgarno sequence would most likely affect which stage of translation in bacteria?

Accepted Answer

Initiation

Question 16

Which of the following best describes the function of release factors (RFs) in translation?

Accepted Answer

They recognize stop codons and promote release of the polypeptide chain.

Question 17

If a tRNA is charged with the wrong amino acid by a faulty aminoacyl-tRNA synthetase, what is the most likely consequence?

Accepted Answer

The wrong amino acid will be incorporated into the growing polypeptide.

Question 18

Which of the following best explains why translation is considered energetically expensive?

Accepted Answer

Each peptide bond formation requires the hydrolysis of multiple high-energy bonds, including GTP and ATP.

Question 19

Which of the following statements about isoacceptor tRNAs is correct?

Accepted Answer

They recognize different codons but carry the same amino acid.

Translation: From RNA to Protein – The Genetic Code and Protein Synthesis

Study Guide - Practice Questions