Question 1

The situation in which an active regulatory protein "turns off" expression is an example of

Accepted Answer

A) positive control. 
B) negative control. 
C) a mutation. 
D) constitutive gene elements. 
E) unique regulation. 
A) positive control. 
B) negative control. 
C) a mutation. 
D) constitutive gene elements. 
E) unique regulation.

Question 2

Of the enzymes associated with the metabolism of lactose with the lac operon, the one associated with transport of lactose into the cell is

Accepted Answer

A) fi galactosidase. 
B) lactose translocase. 
C) transacetylase. 
D) galactoside permease. 
E) fi lactase. 
A) fi galactosidase. 
B) lactose translocase. 
C) transacetylase. 
D) galactoside permease. 
E) fi lactase.

Question 3

Which of the following is an example of translational regulation?

Accepted Answer

A) protein degradation 
B) DNA methylation 
C) protein folding 
D) mRNA degradation 
E) DNA splicing 
A) protein degradation 
B) DNA methylation 
C) protein folding 
D) mRNA degradation 
E) DNA splicing

Question 4

The main chromosome of a bacterial cell possesses the following genotype with regard to the Lac operon: I- O+Z+Y- A- . This bacterial cell would

Accepted Answer

A) make LacZ independently of lactose. 
B) make LacA in the presence of lactose. 
C) make LacZ in the presence of lactose. 
D) make no lac proteins. 
E) make Lac Z and Lac Y in the presence of lactose. 
A) make LacZ independently of lactose. 
B) make LacA in the presence of lactose. 
C) make LacZ in the presence of lactose. 
D) make no lac proteins. 
E) make Lac Z and Lac Y in the presence of lactose.

Question 5

A transcriptional regulator that decreases transcription of a gene from a vast distance is known as a(n)

Accepted Answer

A) nonsense mutation. 
B) silencer. 
C) enhancer. 
D) upstream control element. 
E) regulator. 
A) nonsense mutation. 
B) silencer. 
C) enhancer. 
D) upstream control element. 
E) regulator.

Question 6

The graph below shows a growth curve of E. coli growing in a defined medium containing equal molar amounts of glucose and lactose.   Based on your knowledge of the regulation of the lac operon, the best explanation of these results is that

Accepted Answer

A) the bacteria are utilizing both sugars simultaneously. 
B) early on, due to the presence of lactose, the bacteria utilize the lac operon. Glucose is used later. 
C) the presence of glucose causes the formation of cAMP catabolic repressor protein (CRP)complexes, which shut down the lac operon until the glucose is used up. 
D) glucose is used first. Once glucose becomes limiting, intracellular cAMP increases, forming cAMP- CRP complexes that activate the lac operon to use lactose. 
E) none of the above 
A) the bacteria are utilizing both sugars simultaneously. 
B) early on, due to the presence of lactose, the bacteria utilize the lac operon. Glucose is used later. 
C) the presence of glucose causes the formation of cAMP catabolic repressor protein (CRP)complexes, which shut down the lac operon until the glucose is used up. 
D) glucose is used first. Once glucose becomes limiting, intracellular cAMP increases, forming cAMP- CRP complexes that activate the lac operon to use lactose. 
E) none of the above

Question 7

A lacOc mutant would

Accepted Answer

A) be able to be induced by lactose. 
B) never make lac structural genes. 
C) have repressed expression. 
D) bind receptor protein. 
E) be constitutively expressed. 
A) be able to be induced by lactose. 
B) never make lac structural genes. 
C) have repressed expression. 
D) bind receptor protein. 
E) be constitutively expressed.

Question 8

Which of the following does NOT apply to eukaryotic gene regulation?

Accepted Answer

A) regulation as a result of compartmentalization 
B) mRNA degradation (turnover) 
C) protein folding 
D) gene regulation by attenuation 
E) protein degradation (turnover) 
A) regulation as a result of compartmentalization 
B) mRNA degradation (turnover) 
C) protein folding 
D) gene regulation by attenuation 
E) protein degradation (turnover)

Question 9

The degradation of mRNA in the cells occurs in clusters known as

Accepted Answer

A) P bodies. 
B) nuceoli. 
C) iRNA sites. 
D) N sites. 
E) sRNA regions. 
A) P bodies. 
B) nuceoli. 
C) iRNA sites. 
D) N sites. 
E) sRNA regions.

Question 10

A male is tested for cellular abnormalities. Within each of his cells, the technician notes that there are two Barr bodies present within his cells. As a result he has the genotype

Accepted Answer

A) XO. 
B) XXY. 
C) XY. 
D) XXXY. 
E) XXX. 
A) XO. 
B) XXY. 
C) XY. 
D) XXXY. 
E) XXX.

Question 11

Riboswitches have been observed in

Accepted Answer

A) algae. 
B) prokaryotes. 
C) eukaryotes. 
D) yeast. 
E) fungi. 
A) algae. 
B) prokaryotes. 
C) eukaryotes. 
D) yeast. 
E) fungi.

Question 12

Sigma (a)factors can regulate the initiation of transcription. Which of the following is NOT an example of a regulation?

Accepted Answer

A) Bacteriophages may code for specific a factors that bind the core RNA polymerase and result in recognition of viral promoters. 
B) There are many a sigma factors associated with eukaryotic organisms. 
C) Some a factors recognize genes necessary for nitrogen utilization. 
D) Some a factors recognize promoters for genes whose products are necessary when the organism is under stress, such as heat shock. 
A) Bacteriophages may code for specific a factors that bind the core RNA polymerase and result in recognition of viral promoters. 
B) There are many a sigma factors associated with eukaryotic organisms. 
C) Some a factors recognize genes necessary for nitrogen utilization. 
D) Some a factors recognize promoters for genes whose products are necessary when the organism is under stress, such as heat shock.

Question 13

Effector molecules

Accepted Answer

A) are often small organic molecules. 
B) are associated with induction of enzyme synthesis. 
C) are associated with repression of enzyme synthesis. 
D) induce conformational changes. 
E) all of the above 
A) are often small organic molecules. 
B) are associated with induction of enzyme synthesis. 
C) are associated with repression of enzyme synthesis. 
D) induce conformational changes. 
E) all of the above

Question 14

You are working with a gene associated with an essential pathway that is necessary at two time points in an organism's lifetime. With regard to gene regulation, you would expect the gene to be

Accepted Answer

A) "activated" by particular signals (induced). 
B) not constitutive. 
C) "turned off" by particular signals (repressed). 
D) associated with response to distinct events. 
E) all of the above 
A) "activated" by particular signals (induced). 
B) not constitutive. 
C) "turned off" by particular signals (repressed). 
D) associated with response to distinct events. 
E) all of the above

Question 15

DNA rearrangements in vertebrates occur in the

Accepted Answer

A) viral protein genes. 
B) glycolysis genes. 
C) antibody genes. 
D) cell surface protein genes. 
E) none of the above 
A) viral protein genes. 
B) glycolysis genes. 
C) antibody genes. 
D) cell surface protein genes. 
E) none of the above

The situation in which an active regulatory protein "turns off" expression is an example of

Of the enzymes associated with the metabolism of lactose with the lac operon, the one associated with transport of lactose into the cell is

Which of the following is an example of translational regulation?

The main chromosome of a bacterial cell possesses the following genotype with regard to the Lac operon: I- O+Z+Y- A- . This bacterial cell would

A transcriptional regulator that decreases transcription of a gene from a vast distance is known as a(n)

The graph below shows a growth curve of E. coli growing in a defined medium containing equal molar amounts of glucose and lactose. Based on your knowledge of the regulation of the lac operon, the best explanation of these results is that

A lacOc mutant would

Which of the following does NOT apply to eukaryotic gene regulation?

The degradation of mRNA in the cells occurs in clusters known as

A male is tested for cellular abnormalities. Within each of his cells, the technician notes that there are two Barr bodies present within his cells. As a result he has the genotype

Riboswitches have been observed in

Sigma (a)factors can regulate the initiation of transcription. Which of the following is NOT an example of a regulation?

Effector molecules

You are working with a gene associated with an essential pathway that is necessary at two time points in an organism's lifetime. With regard to gene regulation, you would expect the gene to be

DNA rearrangements in vertebrates occur in the

A Preview of the Cell

The Chemistry of the Cell

The Macromolecules of the Cell

Cells and Organelles

Bioenergetics: The Flow of Energy in the Cell

Enzymes: The Catalysts of Life

Membranes: Their Structure, Function, and Chemistry

Transport Across Membranes: Overcoming the Permeability Barrier

Chemotrophic Energy Metabolism: Glycolysis and Fermentation

Chemotrophic Energy Metabolism: Aerobic Respiration

Phototrophic Energy Metabolism: Photosynthesis

The Endomembrane System and Peroxisomes

Signal Transduction Mechanisms: I Electrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Ii Messengers and Receptors

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesion, Cell Junctions, and Extracellular Structures

The Structural Basis of Cellular Information: DNA, Chromosomes, and the Nucleus

The Cell Cycle, Dna Replication, and Mitosis

Sexual Reproduction, Meiosis, and Genetic Recombination

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Exam 23: The Regulation of Gene Expression

The situation in which an active regulatory protein "turns off" expression is an example of

Of the enzymes associated with the metabolism of lactose with the lac operon, the one associated with transport of lactose into the cell is

Which of the following is an example of translational regulation?

The main chromosome of a bacterial cell possesses the following genotype with regard to the Lac operon: I- O+Z+Y- A- . This bacterial cell would

A transcriptional regulator that decreases transcription of a gene from a vast distance is known as a(n)

The graph below shows a growth curve of E. coli growing in a defined medium containing equal molar amounts of glucose and lactose. Based on your knowledge of the regulation of the lac operon, the best explanation of these results is that

A lacOc mutant would

Which of the following does NOT apply to eukaryotic gene regulation?

The degradation of mRNA in the cells occurs in clusters known as

A male is tested for cellular abnormalities. Within each of his cells, the technician notes that there are two Barr bodies present within his cells. As a result he has the genotype

Riboswitches have been observed in

Sigma (a)factors can regulate the initiation of transcription. Which of the following is NOT an example of a regulation?

Effector molecules

You are working with a gene associated with an essential pathway that is necessary at two time points in an organism's lifetime. With regard to gene regulation, you would expect the gene to be

DNA rearrangements in vertebrates occur in the

A Preview of the Cell

The Chemistry of the Cell

The Macromolecules of the Cell

Cells and Organelles

Bioenergetics: The Flow of Energy in the Cell

Enzymes: The Catalysts of Life

Membranes: Their Structure, Function, and Chemistry

Transport Across Membranes: Overcoming the Permeability Barrier

Chemotrophic Energy Metabolism: Glycolysis and Fermentation

Chemotrophic Energy Metabolism: Aerobic Respiration

Phototrophic Energy Metabolism: Photosynthesis

The Endomembrane System and Peroxisomes

Signal Transduction Mechanisms: I Electrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Ii Messengers and Receptors

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesion, Cell Junctions, and Extracellular Structures

The Structural Basis of Cellular Information: DNA, Chromosomes, and the Nucleus

The Cell Cycle, Dna Replication, and Mitosis

Sexual Reproduction, Meiosis, and Genetic Recombination

Gene Expression: I the Genetic Code and Transcription

Gene Expression: II Protein Synthesis and Sorting

Cancer Cells

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