$$\text{DNA} \rightarrow \text{RNA} \rightarrow \text{Protein}$$

$$\text{Parent DNA (methylated)} \rightarrow \text{Daughter DNA (methylated)}$$

Question 1

Which of the following statements about the wobble position in tRNA is correct?

Accepted Answer

The wobble position enables a single tRNA to recognize multiple codons that encode the same amino acid.

Question 2

A nonsense mutation converts a codon for an amino acid into a stop codon. Which mechanism can counteract the effects of this mutation?

Accepted Answer

Suppresser tRNA

Question 3

Which equation best represents the process of gene expression from DNA to protein?

Accepted Answer

$$	ext{DNA} ightarrow 	ext{RNA} ightarrow 	ext{Protein}$$

Question 4

Which of the following is TRUE regarding DNA methylation?

Accepted Answer

DNA methylation generally leads to chromatin condensation and gene silencing.

Question 5

A protein with a signal peptide but NO other start or stop transfer sequences will most likely:

Accepted Answer

Be fully translocated into the ER lumen and become a soluble protein.

Question 6

Which of the following best describes the effect of histone acetylation on gene expression?

Accepted Answer

Histone acetylation leads to looser chromatin packing and gene activation.

Question 7

Which of the following is a real-life example of DNA methylation leading to gene silencing?

Accepted Answer

X-inactivation in mammals (Barr Body formation)

Question 8

If a protein contains a single internal start transfer sequence, what is its likely fate?

Accepted Answer

It will become a transmembrane protein with the N-terminus in the cytosol and the C-terminus in the ER lumen.

Question 9

Which of the following statements about alternative splicing is correct?

Accepted Answer

Alternative splicing allows a single gene to produce multiple protein isoforms.

Question 10

Which equation represents the inheritance of DNA methylation patterns after DNA replication?

Accepted Answer

$$	ext{Parent DNA (methylated)} ightarrow 	ext{Daughter DNA (methylated)}$$

Question 11

Which of the following is NOT a mechanism for post-transcriptional regulation of gene expression?

Accepted Answer

Histone acetylation

Question 12

A mutation in the stop codon of a gene results in translation read-through. What is the most likely cellular response in eukaryotes?

Accepted Answer

Translation is stalled and the defective mRNA is degraded by an RNA degrading enzyme via nonstop decay.

Question 13

Which of the following best explains how billions of different antibodies can be produced from a limited number of genes?

Accepted Answer

DNA rearrangement and the power of combinations of V, D, and J segments

Question 14

Which of the following is a cis-acting element involved in transcriptional regulation?

Accepted Answer

Enhancer

Question 15

Which of the following is TRUE about the regulation of ferritin translation in response to iron levels?

Accepted Answer

High iron levels increase translation efficiency of ferritin mRNA.

Question 16

Which of the following is a function of the Signal Recognition Particle (SRP) during cotranslational import?

Accepted Answer

SRP binds the ER signal sequence and docks the ribosome on the translocon.

Question 17

Which of the following statements about chromatin structure and gene expression is correct?

Accepted Answer

Condensed chromatin (heterochromatin) is generally associated with gene silencing.

Question 18

Which of the following best describes the role of miRNA in gene expression regulation?

Accepted Answer

miRNA binds to mRNA and inhibits translation or promotes degradation.

Question 19

Which of the following equations best represents the effect of histone acetylation on chromatin structure?

Accepted Answer

$$	ext{Histone acetylation} ightarrow 	ext{Looser chromatin packing} ightarrow 	ext{Gene activation}$$

Gene Expression and Regulation: Mechanisms and Control in Eukaryotic Cells

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