Question 1

Which of the following best describes the role of histone acetylation in eukaryotic gene expression?

Accepted Answer

It promotes loose chromatin structure, making DNA more accessible for transcription.

Question 2

A mutation in the TATA box of a eukaryotic gene would most likely affect which process?

Accepted Answer

The binding of general transcription factors and initiation of transcription.

Question 3

Which RNA polymerase is responsible for transcribing protein-coding genes in eukaryotes?

Accepted Answer

RNA Polymerase II

Question 4

In a yeast cell, the GAL1, GAL7, and GAL10 genes are not clustered together but are coordinately regulated. What enables this coordinated regulation?

Accepted Answer

They each have the same control element upstream that binds the Gal4 transcription factor.

Question 5

Which of the following is TRUE regarding gene expression in archaea?

Accepted Answer

Genes are organized in operons, and the transcription machinery is a simplified version of the eukaryotic system.

Question 6

Which of the following best explains why the PSBO gene is found in all cells of a pea plant, but the PSBO protein is only found in mesophyll cells?

Accepted Answer

All cells contain the same DNA, but gene expression is regulated so that only mesophyll cells produce the protein.

Question 7

A scientist mutates a control element upstream of a gene and observes an increase in reporter gene expression. What type of control element was most likely mutated?

Accepted Answer

A negative control element (repressor binding site)

Question 8

Which of the following is a direct consequence of alternative RNA splicing in eukaryotes?

Accepted Answer

Multiple proteins with different functions can be produced from a single gene.

Question 9

Which process is most likely to result in the fastest change in the amount of a specific protein in a eukaryotic cell?

Accepted Answer

Changing the rate of protein degradation

Question 10

MicroRNAs (miRNAs) regulate gene expression primarily by:

Accepted Answer

Base pairing with target mRNAs to promote their degradation or inhibit their translation.

Question 11

Which of the following best describes the function of mediator proteins in eukaryotic transcription?

Accepted Answer

They mediate interactions between specific transcription factors bound to enhancers and the general transcription machinery at the core promoter.

Question 12

Which of the following statements about eukaryotic gene regulation is FALSE?

Accepted Answer

Eukaryotic genes are often organized in operons for coordinate regulation.

Question 13

A eukaryotic gene is transcribed, but the resulting mRNA is rapidly degraded in the cytoplasm. Which of the following could explain this observation?

Accepted Answer

The mRNA lacks a 5' cap or a poly-A tail.

Question 14

Which of the following is a feature shared by both eukaryotic and archaeal gene expression, but not bacterial gene expression?

Accepted Answer

Presence of histones and chromatin structure.

Question 15

Which of the following equations best represents the steady-state level of mRNA in a eukaryotic cell?

Accepted Answer

$$[	ext{mRNA}] = \frac{	ext{rate of transcription and processing}}{	ext{rate of degradation}}$$

Question 16

Which of the following is the most common mode of alternative splicing in eukaryotes?

Accepted Answer

Exon skipping

Question 17

Which of the following statements about the function of the TATA-binding protein (TBP) is correct?

Accepted Answer

TBP binds to the TATA box and helps recruit general transcription factors and RNA polymerase II to the core promoter.

Question 18

Which of the following best explains why eukaryotic genes are not typically organized in operons?

Accepted Answer

Coordinate regulation is achieved by shared control elements and specific transcription factors rather than physical clustering of genes.

Lecture 20 (Unit 2)-- Regulation of Gene Expression in Eukaryotes and Archaea

Guida di studio - Domande di pratica

Study guide - Flashcard