Question 1

Which molecule acts as the adapter that translates the genetic code from mRNA into a specific amino acid sequence during translation?

Accepted Answer

tRNA

Question 2

What is the primary function of aminoacyl-tRNA synthetase during translation?

Accepted Answer

Attaching the correct amino acid to its corresponding tRNA using ATP

Question 3

During translation, the ribosome moves along the mRNA in which direction?

Accepted Answer

5' to 3'

Question 4

A mutation in the coding region of a gene that changes a single nucleotide but does not alter the amino acid sequence is called:

Accepted Answer

Silent mutation

Question 5

Which of the following best describes the role of rRNA in the ribosome?

Accepted Answer

It acts as a ribozyme, catalyzing peptide bond formation.

Question 6

If a single nucleotide is inserted into the coding region of a gene, what is the most likely consequence?

Accepted Answer

A frameshift mutation

Question 7

Which of the following antibiotics blocks the binding of aminoacyl-tRNA to the A-site of the ribosome?

Accepted Answer

Tetracycline

Question 8

In eukaryotes, what determines whether a ribosome will be free in the cytosol or attached to the rough endoplasmic reticulum?

Accepted Answer

The presence of an N-terminal signal peptide in the protein being synthesized

Question 9

Which of the following codons signals the termination of translation?

Accepted Answer

UAA

Question 10

A point mutation changes the DNA sequence from 5'-GAG-3' to 5'-GTG-3'. What is the effect on the hemoglobin protein?

Accepted Answer

A missense mutation causing sickle cell anemia

Question 11

Which of the following statements about translation is correct?

Accepted Answer

Translation occurs in the 5' to 3' direction along the mRNA.

Question 12

Which of the following best explains why proteins are synthesized from the N-terminus to the C-terminus?

Accepted Answer

Amino acids are attached to tRNA through their carboxyl group, leaving the amino group free for peptide bond formation.

Question 13

Which of the following is NOT a function of tRNA?

Accepted Answer

Catalyzing peptide bond formation

Question 14

In prokaryotes, how are transcription and translation related?

Accepted Answer

They occur simultaneously, often on polycistronic mRNAs.

Question 15

Which of the following best describes a polyribosome?

Accepted Answer

Multiple ribosomes simultaneously translating the same mRNA

Question 16

A frameshift mutation early in the coding region of a gene is most likely to:

Accepted Answer

Alter the entire protein sequence downstream of the mutation

Question 17

Which of the following is true about mutations in non-coding regions?

Accepted Answer

They can affect gene expression and regulation.

Question 18

Which step in translation requires GTP hydrolysis for energy?

Accepted Answer

Initiation and chain elongation

Question 19

Which of the following best describes the effect of a nonsense mutation?

Accepted Answer

It introduces a premature stop codon.

Question 20

Which of the following is a real-world consequence of sickle cell anemia caused by a point mutation in the hemoglobin gene?

Accepted Answer

Crescent-shaped red blood cells that interfere with blood flow, causing anemia and hypoxia

Translation and Point Mutations: Molecular Mechanisms of Protein Synthesis

Study Guide - Practice Questions