Question 1

Which of the following best describes the primary means of regulating gene expression in eukaryotes?

Accepted Answer

Transcriptional control

Question 2

RNA polymerase II is responsible for transcribing which of the following types of RNA?

Accepted Answer

mRNA

Question 3

Which promoter element is most prevalent in highly transcribed eukaryotic genes?

Accepted Answer

TATA box

Question 4

A mutation in the TATA box of a gene would most likely affect which aspect of transcription?

Accepted Answer

The site of transcription initiation

Question 5

Which of the following is a function of enhancer sequences in eukaryotic genes?

Accepted Answer

Increase the frequency of transcription initiation

Question 6

Transcription activators and repressors are described as modular proteins. What does this mean?

Accepted Answer

They contain distinct domains for DNA binding and activation/repression

Question 7

Which of the following histone modifications is associated with transcriptional activation?

Accepted Answer

Acetylation of H3 at lysine 9 ($$\mathrm{H3K9ac})$$

Question 8

A researcher treats cells with a drug that blocks the activity of Polycomb complexes. What is the most likely effect on gene expression?

Accepted Answer

Genes previously repressed by Polycomb complexes may become activated

Question 9

Which of the following best explains why CpG island promoters are characteristic of genes transcribed at a low rate?

Accepted Answer

They lack a TATA box and are regulated by methylation

Question 10

Which of the following statements about epigenetic regulation is correct?

Accepted Answer

It can be maintained after cell division through DNA methylation

Question 11

A mutation in the gene encoding Xist lncRNA would most likely affect which process in female mammals?

Accepted Answer

X-chromosome inactivation

Question 12

Which of the following is a direct result of the binding of a lipid-soluble hormone to its intracellular receptor?

Accepted Answer

Activation of gene expression by binding to response elements in DNA

Question 13

Which of the following best describes the role of general transcription factors in eukaryotic transcription?

Accepted Answer

They are required for the initiation of transcription by RNA polymerase II

Question 14

Which of the following modifications is associated with transcriptional repression?

Accepted Answer

Methylation of H3 at lysine 27 ($$\mathrm{H3K27me3})$$

Question 15

Which of the following is a unique feature of RNA polymerase III compared to RNA polymerase II?

Accepted Answer

It transcribes tRNAs and 5S rRNA

Question 16

A scientist observes that a gene is highly expressed in liver cells but not in neurons. Which of the following is the most likely explanation?

Accepted Answer

The gene's enhancer is bound by liver-specific transcription activators

Question 17

Which of the following best explains the function of DNase I hypersensitive sites (DHSs) in chromatin?

Accepted Answer

They mark regions of open chromatin accessible to transcription factors

Question 18

Which of the following is true regarding the regulation of RNA polymerase II elongation?

Accepted Answer

It can be paused and then activated by phosphorylation events

Question 19

Which of the following statements about the initiation of transcription by RNA polymerase I and III is correct?

Accepted Answer

They require different general transcription factors than RNA polymerase II

Question 20

A mutation that prevents the methylation of H3 at lysine 4 ($$\mathrm{H3K4}) $$would most likely result in which of the following?

Accepted Answer

Reduced activation of gene expression

Transcriptional Control of Gene Expression in Eukaryotes

Study Guide - Practice Questions