Question 1

Which of the following statements is FALSE concerning enrichment bias?

Accepted Answer

A)  Dilution of the inoculum may help to avoid enrichment bias in some cases. 
B)  Enrichment bias is impossible to overcome in some oligotrophic environments. 
C)  Enrichment bias resulted in the underestimation of prokaryotic diversity. 
D)  Enrichment bias favors organisms that grow quickly. 
A)  Dilution of the inoculum may help to avoid enrichment bias in some cases. 
B)  Enrichment bias is impossible to overcome in some oligotrophic environments. 
C)  Enrichment bias resulted in the underestimation of prokaryotic diversity. 
D)  Enrichment bias favors organisms that grow quickly.

Question 2

Single-cell genomics may help us

Accepted Answer

A)  predict which microbes will be abundant based on the environmental conditions. 
B)  understand the physiology of uncultured microbes. 
C)  develop better enrichment culture methods. 
D)  understand the physiology of uncultured microbes and develop better enrichment culture methods. 
A)  predict which microbes will be abundant based on the environmental conditions. 
B)  understand the physiology of uncultured microbes. 
C)  develop better enrichment culture methods. 
D)  understand the physiology of uncultured microbes and develop better enrichment culture methods.

Question 3

Thirty organisms containing the same phylogenetic marker are all considered to be within the same

Accepted Answer

A)  phylotype. 
B)  species. 
C)  functional group. 
D)  phylogenetic tree. 
A)  phylotype. 
B)  species. 
C)  functional group. 
D)  phylogenetic tree.

Question 4

DGGE and T-RFLP are both molecular microbial ecology methods that use the polymerase chain reaction to amplify specific genes to assess diversity.

Accepted Answer

A) True 
 B)False

Question 5

Describe what an ITS region is in the context of prokaryotes,and explain the significance of the ITS region for microbial ecology.

Accepted Answer

The ITS region is the nucleotides betwee

Question 6

Organisms in natural environments can be detected by assaying for the presence of their genes.

Accepted Answer

A) True 
 B)False

Question 7

How do viability stains usually distinguish between living cells and dead cells?

Accepted Answer

A)  The chemical fluoresces only when bound to ribosomes that are actively synthesizing proteins. 
B)  The chemical stain is taken up by living cells and once metabolized becomes fluorescent. 
C)  The dye specifically targets intact cytoplasmic membranes. 
D)  The dye's fluorescence is quenched by dead cells. 
A)  The chemical fluoresces only when bound to ribosomes that are actively synthesizing proteins. 
B)  The chemical stain is taken up by living cells and once metabolized becomes fluorescent. 
C)  The dye specifically targets intact cytoplasmic membranes. 
D)  The dye's fluorescence is quenched by dead cells.

Question 8

Staining methods are suitable for obtaining ________ information about the number of cells in natural samples.

Accepted Answer

A)  qualitative 
B)  quantitative 
C)  both qualitative and quantitative 
D)  neither qualitative nor quantitative 
A)  qualitative 
B)  quantitative 
C)  both qualitative and quantitative 
D)  neither qualitative nor quantitative

Question 9

What technique(s)can be used to characterize the phylogenetic composition of a microbial community without culturing any of the members?

Accepted Answer

A)  green fluorescent protein tagging 
B)  stable isotope techniques 
C)  radioisotope experiments 
D)  fluorescent in situ hybridization 
A)  green fluorescent protein tagging 
B)  stable isotope techniques 
C)  radioisotope experiments 
D)  fluorescent in situ hybridization

Question 10

The science of microbial ecology deals with

Accepted Answer

A)  how microbial communities interact with each other and their environment. 
B)  microbial activity and biodiversity. 
C)  microbial gene regulation mechanisms in response to environmental change. 
D)  how the activity and biodiversity of microbial communities affect microbial interactions with each other and the environment. 
A)  how microbial communities interact with each other and their environment. 
B)  microbial activity and biodiversity. 
C)  microbial gene regulation mechanisms in response to environmental change. 
D)  how the activity and biodiversity of microbial communities affect microbial interactions with each other and the environment.

Question 11

Describe how FISH can be used to determine which cells within a microbial community are actively degrading toluene.Assume the genes involved in the metabolic pathway have been sequenced from several microorganisms and vary only slightly from one another.

Accepted Answer

A conserved gene sequence would need to

Question 12

Combined with autofluoresence or fluorescent DNA probes,flow cytometry can separate or count populations of cells from aquatic environments.

Accepted Answer

A) True 
 B)False

Question 13

Which molecular method allows for the detection of a specific organism within a diverse microbial community?

Accepted Answer

A)  fluorescent DNA staining using DAPI 
B)  viability staining 
C)  enrichment techniques 
D)  fluorescent in situ hybridization 
A)  fluorescent DNA staining using DAPI 
B)  viability staining 
C)  enrichment techniques 
D)  fluorescent in situ hybridization

Question 14

The goal of environmental genomics is to detect as many genes as possible and then,if possible,to determine to the phylogeny of the organisms to which the genes belong.

Accepted Answer

A) True 
 B)False

Question 15

Propose an experiment to identify members capable of assimilating monomers of lignin within a microbial community.

Accepted Answer

SIP could be used,which would require is

Question 16

Diversity is often ________ when ARISA or T-RFLP is used.

Accepted Answer

A)  underestimated 
B)  overestimated 
C)  not represented 
D)  biased 
A)  underestimated 
B)  overestimated 
C)  not represented 
D)  biased

Question 17

How would you label and separate the DNA of unknown methylotrophs in a sample?

Accepted Answer

A)  Incubate the sample with ¹³C-methane. 
B)  Hybridize the DNA to FISH probes. 
C)  Use DGGE to separate the strands of DNA in the sample. 
D)  Use T-RFLP to identify the methylotroph DNA in the sample. 
A)  Incubate the sample with ¹³C-methane. 
B)  Hybridize the DNA to FISH probes. 
C)  Use DGGE to separate the strands of DNA in the sample. 
D)  Use T-RFLP to identify the methylotroph DNA in the sample.

Question 18

Laser tweezers are used for

Accepted Answer

A)  testing the purity of a culture. 
B)  isolating individual cells. 
C)  separating aerobes from anaerobes. 
D)  enhancing the growth of fastidious organisms. 
A)  testing the purity of a culture. 
B)  isolating individual cells. 
C)  separating aerobes from anaerobes. 
D)  enhancing the growth of fastidious organisms.

Question 19

The methodology of microbial ecology includes

Accepted Answer

A)  enrichment and isolation of specific microbes. 
B)  cell-staining methods. 
C)  gene, transcript, and protein characterization. 
D)  enrichment and isolation of specific microbes, cell-staining, and gene, transcript, and protein characterization. 
A)  enrichment and isolation of specific microbes. 
B)  cell-staining methods. 
C)  gene, transcript, and protein characterization. 
D)  enrichment and isolation of specific microbes, cell-staining, and gene, transcript, and protein characterization.

Question 20

We know that that there are over 50 major phyla in Bacteria; however,only about 25 of these phyla have cultured representatives.Why is this? How are scientists attempting to culture representative from the 25 phyla that do not currently have any organisms in culture?

Accepted Answer

We know that more phyla of Bacteria exis

Exam 18: Methods in Microbial Ecology

Which of the following statements is FALSE concerning enrichment bias?

Single-cell genomics may help us

Thirty organisms containing the same phylogenetic marker are all considered to be within the same

DGGE and T-RFLP are both molecular microbial ecology methods that use the polymerase chain reaction to amplify specific genes to assess diversity.

Describe what an ITS region is in the context of prokaryotes,and explain the significance of the ITS region for microbial ecology.

Organisms in natural environments can be detected by assaying for the presence of their genes.

How do viability stains usually distinguish between living cells and dead cells?

Staining methods are suitable for obtaining ________ information about the number of cells in natural samples.

What technique(s)can be used to characterize the phylogenetic composition of a microbial community without culturing any of the members?

The science of microbial ecology deals with

Describe how FISH can be used to determine which cells within a microbial community are actively degrading toluene.Assume the genes involved in the metabolic pathway have been sequenced from several microorganisms and vary only slightly from one another.

Combined with autofluoresence or fluorescent DNA probes,flow cytometry can separate or count populations of cells from aquatic environments.

Which molecular method allows for the detection of a specific organism within a diverse microbial community?

The goal of environmental genomics is to detect as many genes as possible and then,if possible,to determine to the phylogeny of the organisms to which the genes belong.

Propose an experiment to identify members capable of assimilating monomers of lignin within a microbial community.

Diversity is often ________ when ARISA or T-RFLP is used.

How would you label and separate the DNA of unknown methylotrophs in a sample?

Laser tweezers are used for

The methodology of microbial ecology includes

We know that that there are over 50 major phyla in Bacteria; however,only about 25 of these phyla have cultured representatives.Why is this? How are scientists attempting to culture representative from the 25 phyla that do not currently have any organisms in culture?

Microorganisms and Microbiology

Microbial Cell Structure and Function

Microbial Metabolism

Molecular Biology

Microbial Growth and Control

Microbial Genomics

Metabolic Regulation

Viruses and Virology

Viral Genomes and Diversity

Genetics of Bacteria and Archaea

Genetic Engineering and Biotechnology

Microbial Evolution and Systematics

Metabolic Diversity of Microorganisms

Functional Diversity of Bacteria

Diversity of Bacteria

Diversity of Archaea

Diversity of Eukaryotic Microorganisms

Microbial Ecosystems

Nutrient Cycles

Microbiology of the Built Environment

Microbial Symbioses

Microbial Interactions With Humans

Immunity and Host Defense

Immune Mechanisms

Molecular Immunology

Diagnostic Microbiology

Epidemiology

Person-To-Person Bacterial and Viral Diseases

Vectorborne and Soilborne Bacterial and Viral Diseases

Water and Food As Vehicles of Bacterial Diseases

Eukaryotic Pathogens: Fungal and Parasitic Diseases

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