Question 1

Which of the following organisms utilizes polycistronic mRNAs?

Accepted Answer

A) E. coli 
B) C. elegans 
C) mammals 
D) choices A and B only 
E) all of the above 
A) E. coli 
B) C. elegans 
C) mammals 
D) choices A and B only 
E) all of the above

Question 2

When one portion of a chromosome becomes physically part of another chromosome,the type of mutation is referred to as a(n)

Accepted Answer

A) nonsense mutation. 
B) inversion. 
C) translocation. 
D) duplication. 
E) nonstop mutation. 
A) nonsense mutation. 
B) inversion. 
C) translocation. 
D) duplication. 
E) nonstop mutation.

Question 3

In bacteria,a unique RNA that binds the A site of the ribosome and directs the addition of approximately 12 amino acids to the nascent peptide when no stop codon is present is called the ________.

Accepted Answer

tmRNA (tra

Question 4

Typically,the first amino acid incorporated in bacterial protein synthesis is ________.

Accepted Answer

The answer of Typically,the first amino acid incorporated in bacterial...

Question 5

In a mutant E.coli strain,there was a mutation in the malate dehydrogenase gene that resulted in a stop codon at amino acid position 14.From subcultures of this strain,a colony was obtained that was capable of making malate dehydrogenase.Your approach to examining this phenomenon should be to examine

Accepted Answer

A) the DNA sequence to see if a reversion has occurred. 
B) the DNA sequence to see if a suppresor mutation has occurred. 
C) other proteins to see if other stop codons are ignored, indicating the presence of a suppresor tRNA. 
D) the DNA and plasmids for the incorporation of a second complete copy of the malate dehydrogenase gene. 
E) all of the above 
A) the DNA sequence to see if a reversion has occurred. 
B) the DNA sequence to see if a suppresor mutation has occurred. 
C) other proteins to see if other stop codons are ignored, indicating the presence of a suppresor tRNA. 
D) the DNA and plasmids for the incorporation of a second complete copy of the malate dehydrogenase gene. 
E) all of the above

Question 6

Which of the following rRNA molecules is not associated with the large subunit of the eukaryotic ribosome?

Accepted Answer

A) 28S 
B) 5.8S 
C) 5S 
D) 16S 
E) Neither B nor D is associated. 
A) 28S 
B) 5.8S 
C) 5S 
D) 16S 
E) Neither B nor D is associated.

Question 7

In cloning a gene,you discover that the gene product is much longer than should be observed based upon the insert you successfully cloned.What problems would result in a longer cloned sequence? How will you go about investigating your hypothesis? Would your answer change based upon the presence or absence of introns? Why or why not?

Accepted Answer

A variety of possible answers can be gen

Question 8

Which of the following amino acids is not one of the 20 common amino acids found in cells?

Accepted Answer

A) leucine 
B) isoleucine 
C) glutamine 
D) proline 
E) pyrrolysine 
A) leucine 
B) isoleucine 
C) glutamine 
D) proline 
E) pyrrolysine

Question 9

The sequence of amino acids in a protein is based on the ________ of the mRNA.

Accepted Answer

The answer of The sequence of amino acids in a...

Question 10

A mutant bacterium is isolated.This bacterial strain has the characteristic of very slow,"sickly" growth.You isolate mRNA from this bacteria to use in an in vitro translation system and note that even in vitro it is difficult to use this message and obtain protein.Of the following,which is a likely explanation for these results?

Accepted Answer

A) There may be a mutation in the ShineDelgarno sequence of the DNA, resulting in a RNA that poorly binds the ribosome. 
B) There may be a mutation in the ribosomal rRNA recognizing the ShineDelgarno sequence of the message. 
C) This mutant may have altered tRNA molecules, such that the codon-anticodon interaction during translation is affected. 
D) These bacteria may not manufacture enough translation factors for effective translation. 
E) In this mutant, the ribosomal subunits may not associate well enough for effective translation. 
A) There may be a mutation in the ShineDelgarno sequence of the DNA, resulting in a RNA that poorly binds the ribosome. 
B) There may be a mutation in the ribosomal rRNA recognizing the ShineDelgarno sequence of the message. 
C) This mutant may have altered tRNA molecules, such that the codon-anticodon interaction during translation is affected. 
D) These bacteria may not manufacture enough translation factors for effective translation. 
E) In this mutant, the ribosomal subunits may not associate well enough for effective translation.

Question 11

Ribosomes that do not anchor on the surface of the rough endoplasmic reticulum during translation most probably

Accepted Answer

A) are synthesizing cytoplasmic proteins. 
B) have a defect in ribosomal proteins that allow attachment to the surface. 
C) have a signal peptidase error. 
D) do not make the appropriate anchor protein. 
E) all of the above 
A) are synthesizing cytoplasmic proteins. 
B) have a defect in ribosomal proteins that allow attachment to the surface. 
C) have a signal peptidase error. 
D) do not make the appropriate anchor protein. 
E) all of the above

Question 12

All of the following are associated with a protein-folding disease except

Accepted Answer

A) prions. 
B) tau protein. 
C) amyloid plaques. 
D) E-cadherin. 
E) apoplipoprotein E. 
A) prions. 
B) tau protein. 
C) amyloid plaques. 
D) E-cadherin. 
E) apoplipoprotein E.

Question 13

Once an amino acid has been attached to the appropriate tRNA,the tRNA is called a(n)________,and the amino acid is said to be ________.

Accepted Answer

aminoacyl

Question 14

If more than one codon specifies the same amino acid,the code is said to be

Accepted Answer

A) complementary. 
B) inverse. 
C) redundant. 
D) ambiguous. 
E) degenerate. 
A) complementary. 
B) inverse. 
C) redundant. 
D) ambiguous. 
E) degenerate.

Question 15

The ________ allows for flexibility in the codon:anticodon interaction at the third position.

Accepted Answer

The answer of The ________ allows for flexibility in the...

Question 16

AUG is the "start" codon in

Accepted Answer

A) prokaryotic translation. 
B) eukaryotic translation. 
C) both prokaryotic and eukaryotic translation. 
D) neither prokaryotic nor eukaryotic translation. 
E) prokaryotic modification. 
A) prokaryotic translation. 
B) eukaryotic translation. 
C) both prokaryotic and eukaryotic translation. 
D) neither prokaryotic nor eukaryotic translation. 
E) prokaryotic modification.

Question 17

You want to clone a eukaryotic gene and express the protein in yeast.However,the protein typically localizes within mitochondria.How will you perform your gene cloning so that the protein is secreted from the cell,rather than localized within yeast mitochondria?

Accepted Answer

The cloned gene will need to lack the si

Question 18

In bacteria,it is common to produce polycistronic messages,while in eukaryotes it is less common.Describe how polycistronic mRNAs are made and processed in prokaryotes and eukaryotes.How might polycistronic mRNA molecules be an advantage for eukaryotes?

Accepted Answer

In prokaryotes,polycistronic mRNAs typic

Question 19

Shine-Delgarno sequences are present in mRNAs of

Accepted Answer

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

Question 20

Segments of polypeptides that are retained following protein splicing are called

Accepted Answer

A) introns. 
B) exons. 
C) inteins. 
D) exteins. 
E) cleaved. 
A) introns. 
B) exons. 
C) inteins. 
D) exteins. 
E) cleaved.

Exam 22: Gene Expression: Iiprotein Synthesis and Sorting

Which of the following organisms utilizes polycistronic mRNAs?

When one portion of a chromosome becomes physically part of another chromosome,the type of mutation is referred to as a(n)

In bacteria,a unique RNA that binds the A site of the ribosome and directs the addition of approximately 12 amino acids to the nascent peptide when no stop codon is present is called the ________.

Typically,the first amino acid incorporated in bacterial protein synthesis is ________.

Which of the following rRNA molecules is not associated with the large subunit of the eukaryotic ribosome?

Which of the following amino acids is not one of the 20 common amino acids found in cells?

The sequence of amino acids in a protein is based on the ________ of the mRNA.

Ribosomes that do not anchor on the surface of the rough endoplasmic reticulum during translation most probably

All of the following are associated with a protein-folding disease except

Once an amino acid has been attached to the appropriate tRNA,the tRNA is called a(n)________,and the amino acid is said to be ________.

If more than one codon specifies the same amino acid,the code is said to be

The ________ allows for flexibility in the codon:anticodon interaction at the third position.

AUG is the "start" codon in

You want to clone a eukaryotic gene and express the protein in yeast.However,the protein typically localizes within mitochondria.How will you perform your gene cloning so that the protein is secreted from the cell,rather than localized within yeast mitochondria?

In bacteria,it is common to produce polycistronic messages,while in eukaryotes it is less common.Describe how polycistronic mRNAs are made and processed in prokaryotes and eukaryotes.How might polycistronic mRNA molecules be an advantage for eukaryotes?

Shine-Delgarno sequences are present in mRNAs of

Segments of polypeptides that are retained following protein splicing are called

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: Ielectrical and Synaptic Signaling in Neurons

Signal Transduction Mechanisms: Iimessengers and Receptors

Cytoskeletal Systems

Cellular Movement: Motility and Contractility

Beyond the Cell: Cell Adhesions, 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: Ithe Genetic Code and Transcription

The Regulation of Gene Expression

Cancer Cells

Filters

Once an amino acid has been attached to the appropriate tRNA,the tRNA is called a(n),and the amino acid is said to be .