Question 1

Pure cultures can be obtained from an enrichment culture using

Accepted Answer

A)  streak plates only. 
B)  the agar dilution method only. 
C)  liquid dilution methods only. 
D)  streak plates, the agar dilution method, or liquid dilution methods. 
A)  streak plates only. 
B)  the agar dilution method only. 
C)  liquid dilution methods only. 
D)  streak plates, the agar dilution method, or liquid dilution methods. D

Question 2

Stable isotope probing (SIP) is a method that

Accepted Answer

A)  causes cells that hybridize with a fluorescent probe to fluoresce under UV light. 
B)  compares the isotopic ratios of different compounds in the environment to determine whether they are of biological or geological origin. 
C)  uses substrates containing heavy isotopes to label the DNA of organisms that use those substrates. 
D)  compares the transcription of specific isotope labeled genes under different conditions. 
A)  causes cells that hybridize with a fluorescent probe to fluoresce under UV light. 
B)  compares the isotopic ratios of different compounds in the environment to determine whether they are of biological or geological origin. 
C)  uses substrates containing heavy isotopes to label the DNA of organisms that use those substrates. 
D)  compares the transcription of specific isotope labeled genes under different conditions. C

Question 3

What are activity measurements?

Accepted Answer

A)  Activity measurements are any measurements taken in vitro. 
B)  Activity measurements are any measurements taken in situ. 
C)  Activity measurements are collective estimates of the physiological reactions in an entire microbial community. 
D)  Activity measurements are an example of metagenomics, which can be used when genetic analysis is difficult. 
A)  Activity measurements are any measurements taken in vitro. 
B)  Activity measurements are any measurements taken in situ. 
C)  Activity measurements are collective estimates of the physiological reactions in an entire microbial community. 
D)  Activity measurements are an example of metagenomics, which can be used when genetic analysis is difficult. C

Question 4

In natural samples it is often difficult to differentiate live cells from dead cells or cells from nonliving matter without special dyes.

Accepted Answer

A) True 
 B)False

Question 5

The Winogradsky column is a method for assessing the entire gene complement of a habitat, revealing both the biodiversity and metabolic capabilities of the microbial community at the same time.

Accepted Answer

A) True 
 B)False

Question 6

In an agar dilution tube, microbial colonies grow

Accepted Answer

A)  at the bottom of the tube. 
B)  on the sides of the tube, although some may be at the surface. 
C)  embedded in the agar, rather than growing on the surface. 
D)  on the surface, but some creep down the sides away from the surface. 
A)  at the bottom of the tube. 
B)  on the sides of the tube, although some may be at the surface. 
C)  embedded in the agar, rather than growing on the surface. 
D)  on the surface, but some creep down the sides away from the surface.

Question 7

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

Accepted Answer

A) True 
 B)False

Question 8

Which approach would help to identify biologically produced sulfur in a sediment sample?

Accepted Answer

A)  enrichment 
B)  isotopic fractionation 
C)  microautoradiography 
D)  microelectrodes 
A)  enrichment 
B)  isotopic fractionation 
C)  microautoradiography 
D)  microelectrodes

Question 9

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 characterization of genes, transcripts, and proteins. 
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 characterization of genes, transcripts, and proteins.

Question 10

Why is it necessary to have a standard for the interpretation of stable isotope ratios?

Accepted Answer

A)  A standard is necessary to calculate how rapidly the stable isotopes undergo radioactive decay. 
B)  A standard is necessary to determine the stable isotope ratio in the absence of biological activity. 
C)  A standard is necessary because samples are only presented in comparison with other samples of the same age. 
D)  A standard is necessary to determine the age of the sample. 
A)  A standard is necessary to calculate how rapidly the stable isotopes undergo radioactive decay. 
B)  A standard is necessary to determine the stable isotope ratio in the absence of biological activity. 
C)  A standard is necessary because samples are only presented in comparison with other samples of the same age. 
D)  A standard is necessary to determine the age of the sample.

Question 11

Well-designed microbial activity measurements can reveal ________ of major metabolic reactions in a habitat.

Accepted Answer

A)  types 
B)  rates 
C)  both types and rates 
D)  either types or rates (but not both) 
A)  types 
B)  rates 
C)  both types and rates 
D)  either types or rates (but not both)

Question 12

Microarrays are useful for assessing

Accepted Answer

A)  gene expression only. 
B)  enzyme activity. 
C)  the presence of specific rRNA sequences only. 
D)  gene expression and the presence of specific rRNA sequences. 
A)  gene expression only. 
B)  enzyme activity. 
C)  the presence of specific rRNA sequences only. 
D)  gene expression and the presence of specific rRNA sequences.

Question 13

Winogradsky columns are used primarily for enrichment of

Accepted Answer

A)  aerobic cultures, although occasionally anaerobes do appear. 
B)  anaerobic cultures, although occasionally aerobes do appear. 
C)  aerobes, anaerobes, and phototrophs. 
D)  phototrophs, although occasionally heterotrophs do appear. 
A)  aerobic cultures, although occasionally anaerobes do appear. 
B)  anaerobic cultures, although occasionally aerobes do appear. 
C)  aerobes, anaerobes, and phototrophs. 
D)  phototrophs, although occasionally heterotrophs do appear.

Question 14

How can NanoSIMS be used to determine which Roseobacters most strongly use DMSP as a sulfur source within a coastal marine environment? Explain the NanoSIMS methodology in your answer.

Accepted Answer

NanoSIMS is a highly sensitive technique

Question 15

Diversity is often ________ when T-RFLP is used.

Accepted Answer

A)  underestimated 
B)  overestimated 
C)  randomly overestimated or underestimated 
D)  impossible to estimate 
A)  underestimated 
B)  overestimated 
C)  randomly overestimated or underestimated 
D)  impossible to estimate

Question 16

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 17

Interpreting stable isotopic fractionation depends on the fact that most enzymes preferentially bind ________ isotope substrates over ________ isotope substrates.

Accepted Answer

A)  nonradioactive / radioactive 
B)  light / heavy 
C)  heavy / light 
D)  radioactive / nonradioactive 
A)  nonradioactive / radioactive 
B)  light / heavy 
C)  heavy / light 
D)  radioactive / nonradioactive

Question 18

If properly constructed, a Winogradsky column can be used to isolate pure cultures.

Accepted Answer

A) True 
 B)False

Question 19

The overall purpose of DGGE is to

Accepted Answer

A)  separate genes that differ in length. 
B)  measure the activity of cells that use DGGE as an energy source. 
C)  detect cells that utilize a specific radiolabeled substrate. 
D)  separate genes of the same length that have different sequences, resulting in different denaturation profiles. 
A)  separate genes that differ in length. 
B)  measure the activity of cells that use DGGE as an energy source. 
C)  detect cells that utilize a specific radiolabeled substrate. 
D)  separate genes of the same length that have different sequences, resulting in different denaturation profiles.

Question 20

The purpose of the enrichment culture technique is to enrich for organisms with specific physiological properties from a microbial community.

Accepted Answer

A) True 
 B)False

Exam 19: Taking the Measure of Microbial Systems

Pure cultures can be obtained from an enrichment culture using

Stable isotope probing (SIP) is a method that

What are activity measurements?

In natural samples it is often difficult to differentiate live cells from dead cells or cells from nonliving matter without special dyes.

The Winogradsky column is a method for assessing the entire gene complement of a habitat, revealing both the biodiversity and metabolic capabilities of the microbial community at the same time.

In an agar dilution tube, microbial colonies grow

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

Which approach would help to identify biologically produced sulfur in a sediment sample?

The methodology of microbial ecology includes

Why is it necessary to have a standard for the interpretation of stable isotope ratios?

Well-designed microbial activity measurements can reveal ________ of major metabolic reactions in a habitat.

Microarrays are useful for assessing

Winogradsky columns are used primarily for enrichment of

How can NanoSIMS be used to determine which Roseobacters most strongly use DMSP as a sulfur source within a coastal marine environment? Explain the NanoSIMS methodology in your answer.

Diversity is often ________ when T-RFLP is used.

Which of the following statements is FALSE concerning enrichment bias?

Interpreting stable isotopic fractionation depends on the fact that most enzymes preferentially bind ________ isotope substrates over ________ isotope substrates.

If properly constructed, a Winogradsky column can be used to isolate pure cultures.

The overall purpose of DGGE is to

The purpose of the enrichment culture technique is to enrich for organisms with specific physiological properties from a microbial community.

The Microbial World

Microbial Cell Structure and Function

Microbial Metabolism

Molecular Information Flow and Protein Processing

Microbial Growth and Its Control

Microbial Regulatory Systems

Molecular Biology of Microbial Growth

Viruses and Their Replication

Microbial Systems Biology

Viral Genomics, Diversity, and Ecology

Genetics of Bacteria and Archaea

Biotechnology and Synthetic Biology

Microbial Evolution and Systematics

Metabolic Diversity of Microorganisms

Functional Diversity of Microorganisms

Diversity of Bacteria

Diversity of Archaea

Diversity of Microbial Eukarya

Microbial Ecosystems

Nutrient Cycles

Microbiology of the Built Environment

Microbial Symbioses

Microbial Symbioses with Humans

Microbial Infection and Pathogenesis

Innate Immunity: Broadly Specific Host Defenses

Adaptive Immunity: Highly Specific Host Defenses

Clinical Microbiology and Immunology

Epidemiology

Person-to-Person Bacterial and Viral Diseases

Vectorborne and Soilborne Bacterial and Viral Diseases

Waterborne and Foodborne Bacterial and Viral Diseases

Eukaryotic Pathogens: Fungi, Protozoans, and Helminths

Filters

Interpreting stable isotopic fractionation depends on the fact that most enzymes preferentially bind isotope substrates over isotope substrates.