Question 1

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

Accepted Answer

The conversion of mRNA sequence into a polypeptide chain

Question 2

What is the main function of tRNA during translation?

Accepted Answer

To deliver specific amino acids to the ribosome according to the mRNA codon

Question 3

Which statement about the genetic code is CORRECT?

Accepted Answer

The genetic code is degenerate, meaning multiple codons can encode the same amino acid

Question 4

Which scientists are credited with deciphering the first codon of the genetic code using synthetic RNA?

Accepted Answer

Marshall Nirenberg and Johann Matthaei

Question 5

Why is the genetic code described as 'universal'?

Accepted Answer

It was established early in evolution and is nearly the same in most organisms

Question 6

What is the wobble hypothesis?

Accepted Answer

It describes the flexibility in base pairing at the third position of the codon

Question 7

Which of the following is a consequence of the degeneracy of the genetic code?

Accepted Answer

Chemically similar amino acids are often encoded by related codons

Question 8

Aminoacyl-tRNA synthetases are responsible for which critical step in translation?

Accepted Answer

Attaching the correct amino acid to its corresponding tRNA

Question 9

Which of the following is NOT a typical binding site on an aminoacyl-tRNA synthetase?

Accepted Answer

Ribosomal protein

Question 10

Suppose a mutation creates a suppressor tRNA with an anticodon that recognizes a stop codon. What is the likely result?

Accepted Answer

Insertion of an amino acid at the stop codon, resulting in a longer protein

Question 11

Which ribosomal RNA plays a direct role in catalyzing peptide bond formation during translation?

Accepted Answer

23S rRNA

Question 12

A tRNA with the anticodon 3'-CAI-5' can recognize which codons due to wobble pairing?

Accepted Answer

$$5'-GUA-3'$$, $$5'-GUC-3'$$, and $$5'-GUU-3'$$

Question 13

Which of the following is a potential risk of efficient suppression of nonsense mutations by suppressor tRNAs?

Accepted Answer

Readthrough past normal termination codons, producing abnormally long proteins

Question 14

What is the main reason that aminoacyl-tRNA synthetases do NOT use the anticodon as the primary determinant for tRNA recognition?

Accepted Answer

There are multiple tRNAs with different anticodons for the same amino acid

Question 15

Which of the following errors in translation is most common?

Accepted Answer

Incorrect aminoacyl-tRNA mispairing with a codon

Question 16

In E. coli, there are 43 tRNAs for 61 sense codons. What molecular mechanism explains this discrepancy?

Accepted Answer

The wobble hypothesis, allowing some tRNAs to recognize multiple codons

Question 17

Which of the following is TRUE regarding ribosomal RNA (rRNA) in the ribosome?

Accepted Answer

rRNA forms the catalytic core and mediates most contacts between subunits

Question 18

A mutation in the anticodon of a tRNA that allows it to recognize a different codon and insert the wrong amino acid is called:

Accepted Answer

A missense suppressor

Question 19

Which of the following best explains why some anticodons are not made in cells?

Accepted Answer

They would result in ambiguous decoding of codons, leading to translation errors

Translation and the Genetic Code: Structure, Function, and Mechanisms

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