Question 1

Why is replication of the lagging DNA strand a problem, and how is this problem overcome?

Accepted Answer

DNA polymerase can only add nucleotides

Question 2

The sliding clamp is used to ________ and is loaded by ________.

Accepted Answer

A)  open the helix; clamp-loading complex 
B)  open the helix; DNA polymerase III 
C)  tether the DNA polymerase to the chromosome; clamp-loading complex 
D)  tether the DNA polymerase to the chromosome; DNA polymerase I 
E)  tether the polymerase to the chromosome; DNA primase 
A)  open the helix; clamp-loading complex 
B)  open the helix; DNA polymerase III 
C)  tether the DNA polymerase to the chromosome; clamp-loading complex 
D)  tether the DNA polymerase to the chromosome; DNA polymerase I 
E)  tether the polymerase to the chromosome; DNA primase

Question 3

Which of the following is true in the DNA double helix?

Accepted Answer

A)  The strands are parallel. 
B)  Phosphate groups are located at the 5'-ends of both strands. 
C)  Adenine complements cytosine. 
D)  Guanine complements thymine. 
E)  Only major grooves can be formed. 
A)  The strands are parallel. 
B)  Phosphate groups are located at the 5'-ends of both strands. 
C)  Adenine complements cytosine. 
D)  Guanine complements thymine. 
E)  Only major grooves can be formed.

Question 4

How are archaeal genomes and gene expression mechanisms similar to both bacterial and eukaryotic genomes?

Accepted Answer

Like bacteria, reproduction in archaea i

Question 5

The ability of cohesive ends of DNA from different organisms to ________ constitutes the basis of recombinant DNA technology.

Accepted Answer

A)  be methylated 
B)  be specifically cut 
C)  form complementary base pairs 
D)  repel each other 
E)  be sequenced 
A)  be methylated 
B)  be specifically cut 
C)  form complementary base pairs 
D)  repel each other 
E)  be sequenced

Question 6

The natural function of ________ is to cut the DNA of invading plasmids and phages at specific sequences.

Accepted Answer

A)  topoisomerases 
B)  restriction endonucleases 
C)  ligases 
D)  RNases 
E)  gyrases 
A)  topoisomerases 
B)  restriction endonucleases 
C)  ligases 
D)  RNases 
E)  gyrases

Question 7

Hyperthermophilic archaea possess an unusual gyrase called ________, which introduces positive supercoils into the chromosome in order to protect the DNA from ________.

Accepted Answer

A)  reverse DNA gyrase; thermal denaturation 
B)  DNA helicase; thermal denaturation 
C)  topoisomerase I; gene overexpression 
D)  DNA ligase; thermal denaturation 
E)  reverse transcriptase; gene overexpression 
A)  reverse DNA gyrase; thermal denaturation 
B)  DNA helicase; thermal denaturation 
C)  topoisomerase I; gene overexpression 
D)  DNA ligase; thermal denaturation 
E)  reverse transcriptase; gene overexpression

Question 8

The main replication DNA polymerase in E. coli is Pol III. What type of bonds do DNA polymerases form?

Accepted Answer

A)  aminoacyl-tRNA 
B)  peptide 
C)  phosphodiester 
D)  hydrogen 
E)  disulfide 
A)  aminoacyl-tRNA 
B)  peptide 
C)  phosphodiester 
D)  hydrogen 
E)  disulfide

Question 9

Which molecule is responsible for removing torsional stress during DNA replication?

Accepted Answer

A)  DNA primase 
B)  single-stranded binding proteins 
C)  RNase H 
D)  DNA gyrase 
E)  DNA ligase 
A)  DNA primase 
B)  single-stranded binding proteins 
C)  RNase H 
D)  DNA gyrase 
E)  DNA ligase

Question 10

Which of the following is NOT true about histones?

Accepted Answer

A)  They are rich in arginine and lysine. 
B)  They bind to negatively charged DNA. 
C)  They are positively charged. 
D)  They are used to control expression of bacterial operons. 
E)  They form units with DNA called nucleosomes. 
A)  They are rich in arginine and lysine. 
B)  They bind to negatively charged DNA. 
C)  They are positively charged. 
D)  They are used to control expression of bacterial operons. 
E)  They form units with DNA called nucleosomes.

Question 11

What is metagenomics? How have the methods of metagenomics allowed discovery of so many new species? How is it possible to know about these organisms without being able to grow them in a laboratory?

Accepted Answer

Metagenomics is the use of modern genomi

Question 12

Which of the following is an INCORRECT statement about pseudogenes?

Accepted Answer

A)  Portions of their DNA sequences are similar to those of genes with known functions. 
B)  RNA can be transcribed from some pseudogenes, but the protein products will not have an obvious function. 
C)  Pseudogenes are lost more quickly in bacteria because of their faster replication processes. 
D)  Bacterial pseudogenes account for less of the genome than in eukaryotes. 
E)  Pseudogenes have not been found in bacteria. 
A)  Portions of their DNA sequences are similar to those of genes with known functions. 
B)  RNA can be transcribed from some pseudogenes, but the protein products will not have an obvious function. 
C)  Pseudogenes are lost more quickly in bacteria because of their faster replication processes. 
D)  Bacterial pseudogenes account for less of the genome than in eukaryotes. 
E)  Pseudogenes have not been found in bacteria.

Question 13

During replication, the lagging strand is synthesized ________, while the leading strand can be synthesized ________.

Accepted Answer

A)  continuously; discontinuously 
B)  discontinuously; continuously 
C)  5'-to-3'; 3'-to-5' 
D)  3'-to-5'; 5'-to-3' 
E)  quickly; slowly 
A)  continuously; discontinuously 
B)  discontinuously; continuously 
C)  5'-to-3'; 3'-to-5' 
D)  3'-to-5'; 5'-to-3' 
E)  quickly; slowly

Question 14

What is horizontal gene transfer and how does it differ from vertical gene transfer? Is horizontal gene transfer limited to bacteria and archaea?

Accepted Answer

In vertical transfer, genetic informatio

Question 15

Plasmids are NOT

Accepted Answer

A)  found in archaea. 
B)  found in bacteria. 
C)  found in eukaryotes. 
D)  supercoiled. 
E)  usually circular. 
A)  found in archaea. 
B)  found in bacteria. 
C)  found in eukaryotes. 
D)  supercoiled. 
E)  usually circular.

Question 16

How can plasmids ensure that they are passed on from one generation to the next?

Accepted Answer

Some plasmids are high-copy-number, mean

Question 17

Gene transfer from parent to progeny is called

Accepted Answer

A)  expression. 
B)  horizontal gene transfer. 
C)  vertical gene transfer. 
D)  transformation. 
E)  recombination. 
A)  expression. 
B)  horizontal gene transfer. 
C)  vertical gene transfer. 
D)  transformation. 
E)  recombination.

Question 18

________ is an enzyme that may have evolved from ancient progenitor cells with an RNA genome, and it functions as a ________.

Accepted Answer

A)  Primase; helicase 
B)  Primase; reverse transcriptase 
C)  Telomerase; helicase 
D)  Telomerase; reverse transcriptase 
E)  Telomerase; methylator and acetylator 
A)  Primase; helicase 
B)  Primase; reverse transcriptase 
C)  Telomerase; helicase 
D)  Telomerase; reverse transcriptase 
E)  Telomerase; methylator and acetylator

Question 19

A collection of genes and operons whose expression is controlled by a single protein is called a(n)

Accepted Answer

A)  regulon. 
B)  monocistronic message. 
C)  polycistronic message. 
D)  intron. 
E)  exon. 
A)  regulon. 
B)  monocistronic message. 
C)  polycistronic message. 
D)  intron. 
E)  exon.

Question 20

Which of the following is an INCORRECT statement?

Accepted Answer

A)  Reproduction in archaea is predominantly asexual. 
B)  RNA polymerase components of the archaeon Sulfolobus are homologous to those of eukaryotic RNA Pol II. 
C)  All known archaea have a single circular chromosome and genes organized in operons. 
D)  Archaeal DNA-packing proteins and ribosomal components closely resemble those of eukaryotes. 
E)  Both archaeal and eukaryotic genomes encode metabolic pathways of methanogenesis. 
A)  Reproduction in archaea is predominantly asexual. 
B)  RNA polymerase components of the archaeon Sulfolobus are homologous to those of eukaryotic RNA Pol II. 
C)  All known archaea have a single circular chromosome and genes organized in operons. 
D)  Archaeal DNA-packing proteins and ribosomal components closely resemble those of eukaryotes. 
E)  Both archaeal and eukaryotic genomes encode metabolic pathways of methanogenesis.

Exam 7: Genomes and Chromosomes

Why is replication of the lagging DNA strand a problem, and how is this problem overcome?

The sliding clamp is used to ________ and is loaded by ________.

Which of the following is true in the DNA double helix?

How are archaeal genomes and gene expression mechanisms similar to both bacterial and eukaryotic genomes?

The ability of cohesive ends of DNA from different organisms to ________ constitutes the basis of recombinant DNA technology.

The natural function of ________ is to cut the DNA of invading plasmids and phages at specific sequences.

Hyperthermophilic archaea possess an unusual gyrase called ________, which introduces positive supercoils into the chromosome in order to protect the DNA from ________.

The main replication DNA polymerase in E. coli is Pol III. What type of bonds do DNA polymerases form?

Which molecule is responsible for removing torsional stress during DNA replication?

Which of the following is NOT true about histones?

What is metagenomics? How have the methods of metagenomics allowed discovery of so many new species? How is it possible to know about these organisms without being able to grow them in a laboratory?

Which of the following is an INCORRECT statement about pseudogenes?

During replication, the lagging strand is synthesized ________, while the leading strand can be synthesized ________.

What is horizontal gene transfer and how does it differ from vertical gene transfer? Is horizontal gene transfer limited to bacteria and archaea?

Plasmids are NOT

How can plasmids ensure that they are passed on from one generation to the next?

Gene transfer from parent to progeny is called

________ is an enzyme that may have evolved from ancient progenitor cells with an RNA genome, and it functions as a ________.

A collection of genes and operons whose expression is controlled by a single protein is called a(n)

Which of the following is an INCORRECT statement?

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters

The sliding clamp is used to and is loaded by .

Hyperthermophilic archaea possess an unusual gyrase called , which introduces positive supercoils into the chromosome in order to protect the DNA from .

During replication, the lagging strand is synthesized , while the leading strand can be synthesized .

is an enzyme that may have evolved from ancient progenitor cells with an RNA genome, and it functions as a .