Question 1

Which of the following best describes the process of translation in the central dogma of molecular biology?

Accepted Answer

The synthesis of a polypeptide using the information in mRNA

Question 2

During translation, which molecule acts as the 'translator' that matches mRNA codons to their corresponding amino acids?

Accepted Answer

Transfer RNA (tRNA)

Question 3

A mutation changes the codon UUU in mRNA to UUC. Both codons code for phenylalanine. What is this type of mutation called, and why does it not affect the protein sequence?

Accepted Answer

Silent mutation; the genetic code is redundant

Question 4

Which of the following statements about ribosomes is correct?

Accepted Answer

Ribosomes are made of proteins and rRNA and are essential for protein synthesis

Question 5

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

Accepted Answer

It attaches the correct amino acid to its corresponding tRNA

Question 6

A scientist labels methionine with a radioactive isotope and tracks its incorporation into a growing polypeptide. At which site of the ribosome is the methionine-tRNA first located during translation initiation?

Accepted Answer

P site

Question 7

Which of the following best explains the 'wobble' hypothesis in tRNA anticodon-codon pairing?

Accepted Answer

The third base of the codon can form non-standard base pairs, allowing one tRNA to recognize multiple codons

Question 8

During translation elongation, which of the following events occurs immediately after a new aminoacyl-tRNA enters the A site of the ribosome?

Accepted Answer

A peptide bond is formed between the amino acid in the A site and the growing polypeptide in the P site

Question 9

Which of the following codons is a stop codon that signals termination of translation?

Accepted Answer

UAA

Question 10

A polyribosome (polysome) is best described as:

Accepted Answer

Multiple ribosomes translating the same mRNA molecule simultaneously

Question 11

If a tRNA with the anticodon $$5'	ext{GAA}3' is $$present, which mRNA codon will it recognize?

Accepted Answer

$$5'	ext{CUU}3'$$

Question 12

Which of the following best describes the direction in which mRNA is read during translation?

Accepted Answer

$$5' \rightarrow 3'$$

Question 13

A mutation in the gene encoding an aminoacyl-tRNA synthetase causes it to attach the wrong amino acid to a tRNA. What is the most likely consequence?

Accepted Answer

The wrong amino acid will be incorporated into the protein, potentially altering its function

Question 14

Which of the following steps requires energy in the form of GTP during translation?

Accepted Answer

Translocation of the ribosome along the mRNA

Question 15

After translation is terminated, which of the following processes is most likely to occur to the newly synthesized polypeptide?

Accepted Answer

It folds into its functional three-dimensional shape, sometimes with the help of chaperone proteins

Question 16

Which of the following best explains why there are fewer tRNA types than codons?

Accepted Answer

The wobble position allows some tRNAs to pair with more than one codon

Question 17

Which of the following is NOT a function of ribosomal RNA (rRNA) in the ribosome?

Accepted Answer

Carrying amino acids to the ribosome

Question 18

A patient has a genetic disorder that prevents the addition of a 5' cap and poly-A tail to mRNA. What is the most likely effect on translation?

Accepted Answer

The mRNA will be unstable and degraded quickly, reducing protein synthesis

Question 19

Which of the following best describes the role of a release factor during translation termination?

Accepted Answer

It adds a water molecule to the polypeptide, releasing it from the tRNA

Question 20

Which of the following is a real-world example of post-translational modification?

Accepted Answer

The folding of hemoglobin subunits and their assembly into a functional protein

Translation: From Nucleic Acid to Amino Acid (Chapter 17.3–17.5) – The Molecular Basis of Protein Synthesis

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