Question 1

Which of the following best describes the role of enhancers in eukaryotic gene regulation?

Accepted Answer

Enhancers are regulatory DNA elements that can increase transcription of genes, often acting at a distance from the promoter.

Question 2

A researcher uses a reporter transgene to study the activity of a suspected enhancer. Which result would best indicate that the DNA fragment contains an active enhancer?

Accepted Answer

The reporter gene is expressed in a specific tissue or developmental stage, matching the pattern of the endogenous gene.

Question 3

Which of the following statements about combinatorial control of gene expression is correct?

Accepted Answer

Combinatorial control refers to the integration of multiple transcription factors binding to regulatory elements to determine gene expression.

Question 4

Which of the following is a key property of modularity in enhancers?

Accepted Answer

Each enhancer typically regulates a specific aspect of a gene's expression pattern, allowing independent evolution of gene regulation.

Question 5

A mutation in a Drosophila yellow gene enhancer affects pigmentation only in the wings, but not in the body or bristles. What does this observation best illustrate?

Accepted Answer

Enhancer modularity, where different enhancers control gene expression in different tissues.

Question 6

Which of the following best describes the function of the activation domain of a transcription factor?

Accepted Answer

It interacts with other components of the transcriptional machinery to increase gene expression.

Question 7

Which experimental technique is used to identify DNA regions bound by specific proteins in vivo, and can be followed by sequencing to map binding sites genome-wide?

Accepted Answer

Chromatin immunoprecipitation followed by sequencing (ChIP-seq)

Question 8

Which of the following equations correctly represents the probability $$P of a $$gene being expressed in a cell, given that it requires the presence of two independent transcription factors $$A$$ and $$B$$, each present with probability $$p_A$$ and $$p_B$$ respectively?

Accepted Answer

$$P = p_A 	imes p_B$$

Question 9

Steroid hormone signaling differs from peptide hormone signaling in that steroid hormones:

Accepted Answer

Diffuse through the cell membrane and bind to intracellular receptors that directly regulate gene expression.

Question 10

Which of the following statements about transcription factors is FALSE?

Accepted Answer

They always bind RNA directly to regulate gene expression.

Question 11

In a ChIP-seq experiment, what does a 'peak' in the data typically represent?

Accepted Answer

A region of the genome where the protein of interest is bound.

Question 12

Which of the following best explains why combinatorial control is important for multicellular organisms?

Accepted Answer

It enables precise spatial and temporal regulation of gene expression in different cell types.

Question 13

Which of the following is NOT a typical property of enhancers?

Accepted Answer

They always act only in the tissue where the gene is expressed.

Question 14

A scientist deletes a specific enhancer of a gene in mice and observes that the gene is no longer expressed in the liver, but expression in other tissues is unaffected. What does this result suggest?

Accepted Answer

The deleted enhancer is specifically required for liver expression, demonstrating enhancer modularity.

Question 15

Which of the following best describes the difference between constitutive and regulated gene expression?

Accepted Answer

Constitutive genes are always expressed, while regulated genes are expressed only under certain conditions or in specific cell types.

Question 16

Which of the following is a correct statement about the use of reporter transgenes in enhancer identification?

Accepted Answer

Reporter transgenes allow visualization of the spatial and temporal activity of candidate enhancers.

Question 17

Which of the following signaling pathways is most likely to involve direct activation of gene expression by a hormone-receptor complex binding to DNA?

Accepted Answer

Steroid hormone signaling

Question 18

Which of the following best describes the outcome of a mutation in a tissue-specific enhancer of the Drosophila yellow gene?

Accepted Answer

Pigmentation is lost only in the tissue where the enhancer is normally active.

Question 19

Which of the following is a key advantage of using ChIP-seq over traditional reporter assays for studying gene regulation?

Accepted Answer

ChIP-seq can provide genome-wide maps of protein-DNA interactions in vivo.

Regulation of Eukaryotic Transcription: Mechanisms and Methods

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