Question 1

Which of the following best describes the role of tRNA during translation?

Accepted Answer

tRNA brings specific amino acids to the ribosome by recognizing codons in the mRNA through its anticodon loop.

Question 2

A mutation causes the insertion of a single nucleotide into a gene. What is the most likely effect on the resulting protein?

Accepted Answer

It will cause a frameshift mutation, altering the reading frame and likely changing all downstream amino acids.

Question 3

Which property of the genetic code allows a single amino acid to be encoded by more than one codon?

Accepted Answer

Degeneracy

Question 4

What is the function of the Shine-Dalgarno sequence in prokaryotic translation initiation?

Accepted Answer

It serves as the binding site for the ribosome by base-pairing with the 16S rRNA.

Question 5

Which of the following statements about peptide bond formation is correct?

Accepted Answer

Peptide bonds are covalent bonds formed between the carboxyl group of one amino acid and the amino group of the next.

Question 6

Which experiment provided genetic evidence that the genetic code is read in triplets?

Accepted Answer

Crick and Brenner’s proflavin-induced mutation experiments in bacteriophage T4.

Question 7

If the mRNA codon is 5'-CUC-3', what is the sequence of the anticodon on the tRNA that recognizes it?

Accepted Answer

3'-GAG-5'

Question 8

Which of the following is NOT a property of the genetic code?

Accepted Answer

It is ambiguous, with each codon specifying more than one amino acid.

Question 9

During translation elongation, what provides the energy for the translocation of the ribosome along the mRNA?

Accepted Answer

GTP hydrolysis by elongation factor G (EF-G).

Question 10

Which of the following best explains why the third base in a codon is called the 'wobble' position?

Accepted Answer

It can form non-standard base pairs, allowing some tRNAs to recognize multiple codons.

Question 11

A mutation changes the DNA sequence from 5'-GAA-3' to 5'-GAG-3'. Both codons code for glutamic acid. What type of mutation is this?

Accepted Answer

Silent mutation

Question 12

Which of the following is true regarding the start codon in translation?

Accepted Answer

The start codon is AUG, which codes for methionine.

Question 13

Which enzyme is responsible for 'charging' tRNAs with their corresponding amino acids?

Accepted Answer

Aminoacyl-tRNA synthetase

Question 14

What is the main chemical difference between the N-terminus and C-terminus of a polypeptide?

Accepted Answer

The N-terminus has a free amino group, and the C-terminus has a free carboxyl group.

Question 15

Which of the following statements about ribosomes is correct?

Accepted Answer

The rRNA in the ribosome catalyzes peptide bond formation, making the ribosome a ribozyme.

Question 16

A patient has a mutation that changes a codon from UAU (tyrosine) to UAA (stop). What is the most likely effect?

Accepted Answer

The protein will be truncated due to premature termination.

Question 17

Which of the following best describes the flow of genetic information in the central dogma?

Accepted Answer

DNA → RNA → Protein

Question 18

Which of the following amino acids is encoded by only one codon?

Accepted Answer

Methionine

Question 19

Which of the following is a direct result of the degeneracy of the genetic code?

Accepted Answer

Multiple codons can encode the same amino acid.

Question 20

Which of the following is NOT required for translation to occur?

Accepted Answer

DNA polymerase

Translation and the Genetic Code: From DNA to Protein

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