Question 1

Nonphotosynthetic ________ provide minerals and protection for lichen symbiotic partners.

Accepted Answer

A)  plankton 
B)  proteobacteria 
C)  algae 
D)  fungi 
E)  cyanobacteria 
A)  plankton 
B)  proteobacteria 
C)  algae 
D)  fungi 
E)  cyanobacteria D

Question 2

Which term represents the region of soil influenced by plant roots?

Accepted Answer

A)  stele 
B)  cortex 
C)  root cap 
D)  rhizoplane 
E)  rhizosphere 
A)  stele 
B)  cortex 
C)  root cap 
D)  rhizoplane 
E)  rhizosphere E

Question 3

Most forest trees require mycorrhizae for growth because

Accepted Answer

A)  forest soils are rich in phosphorous. 
B)  mycorrhizae limit toxic metal uptake. 
C)  the mycorrhizal form an ammensalic association. 
D)  mycorrhizae significantly increase the uptake of nutrients. 
E)  forest trees do not have deep roots. 
A)  forest soils are rich in phosphorous. 
B)  mycorrhizae limit toxic metal uptake. 
C)  the mycorrhizal form an ammensalic association. 
D)  mycorrhizae significantly increase the uptake of nutrients. 
E)  forest trees do not have deep roots. D

Question 4

The ________ region of an oligotrophic lake extends to about 10 meters below the surface.

Accepted Answer

A)  neuston 
B)  benthic 
C)  epilimnion 
D)  hypolimnion 
E)  euphotic 
A)  neuston 
B)  benthic 
C)  epilimnion 
D)  hypolimnion 
E)  euphotic

Question 5

Eutrophic lakes typically support ten times the microbial concentrations of an oligotrophic lake. Which of the following statements is NOT true of eutrophic lakes?

Accepted Answer

A)  Biochemical oxygen demand is high. 
B)  Population of aquatic animals is high. 
C)  Nitrogen and phosphorous levels are usually high. 
D)  Photosynthetic activities are altered. 
E)  Algal blooms are common. 
A)  Biochemical oxygen demand is high. 
B)  Population of aquatic animals is high. 
C)  Nitrogen and phosphorous levels are usually high. 
D)  Photosynthetic activities are altered. 
E)  Algal blooms are common.

Question 6

Compared to eutrophic lakes, the biochemical oxygen demand, or BOD, of oligotrophic lakes is

Accepted Answer

A)  low. 
B)  similar. 
C)  high. 
D)  unpredictable. 
E)  extremely high. 
A)  low. 
B)  similar. 
C)  high. 
D)  unpredictable. 
E)  extremely high.

Question 7

Name two factors that differentiate aquatic and terrestrial ecosystems and explain how they affect food cycles in these systems.

Accepted Answer

A major difference appears between marin

Question 8

In the legume-rhizobium symbiosis, nitrogen fixation is carried out in nodules by

Accepted Answer

A)  bacteroids that lack a cell wall. 
B)  intact rhizobia in the plant cortex. 
C)  plant cells in the presence of symbiotic bacteria. 
D)  bacteroids in oxygen-rich nodules. 
E)  photosynthetic bacteroids in plants. 
A)  bacteroids that lack a cell wall. 
B)  intact rhizobia in the plant cortex. 
C)  plant cells in the presence of symbiotic bacteria. 
D)  bacteroids in oxygen-rich nodules. 
E)  photosynthetic bacteroids in plants.

Question 9

Describe the steps in sequencing a metagenome.

Accepted Answer

You first sample the microbial target co

Question 10

The following image illustrates a syntrophic relationship between an archaeon and a bacterium. The technique used to generate this image was

Accepted Answer

A)  light microscopy. 
B)  transmission electron microscopy. 
C)  metagenomics. 
D)  fluorescence in situ hybridization. 
E)  atomic force microscopy. 
A)  light microscopy. 
B)  transmission electron microscopy. 
C)  metagenomics. 
D)  fluorescence in situ hybridization. 
E)  atomic force microscopy.

Question 11

In any environment, pathogens are always outnumbered by a vast community of neutral or helpful microbes. Describe some beneficial as well as devastating incidences of plant pathogens.

Accepted Answer

Answers may vary. A plant virus is assoc

Question 12

How do metatranscriptomics and metaproteomics address functional limitations of metagenomics?

Accepted Answer

Metatranscriptomics, the study of the RN

Question 13

What is coral bleaching? What is its possible cause?

Accepted Answer

Coral bleaching occurs when coral zooxan

Question 14

The availability of oxygen and other electron acceptors is the most important determinant of the types of metabolism in a habitat. Which of the following is NOT true about anaerobic environments?

Accepted Answer

A)  They have slower rates of assimilation compared to aerobic habitats. 
B)  Their rates of dissimilation are slower compared to aerobic environments. 
C)  Microbes sometimes use minerals such as NO2- to oxidize organic compounds. 
D)  Anaerobic microbial biomass far exceeds that of the oxygenated biosphere. 
E)  Respiration of organic compounds is highly dissimilatory, reducing them to CO2. 
A)  They have slower rates of assimilation compared to aerobic habitats. 
B)  Their rates of dissimilation are slower compared to aerobic environments. 
C)  Microbes sometimes use minerals such as NO2- to oxidize organic compounds. 
D)  Anaerobic microbial biomass far exceeds that of the oxygenated biosphere. 
E)  Respiration of organic compounds is highly dissimilatory, reducing them to CO2.

Question 15

Define BOD, and explain why it can be used to measure the pollution level of lakes. Describe how effluents carrying high levels of nutrients can cause eutrophication.

Accepted Answer

BOD is an abbreviation for biochemical o

Question 16

Compare and contrast the photic zones of freshwater lake and pelagic ecosystems.

Accepted Answer

The photic zone in the marine habitat is

Question 17

A holobiont is defined as an

Accepted Answer

A)  organism that benefits while providing no benefit or a hidden benefit to its host. 
B)  interaction that harms one partner nonspecifically without an intimate symbiosis. 
C)  organism that forms an intimate relationship with another, where both benefit. 
D)  entity composed of multiple types of organisms, including microbes. 
E)  intimate relationship in which one member benefits while harming a host. 
A)  organism that benefits while providing no benefit or a hidden benefit to its host. 
B)  interaction that harms one partner nonspecifically without an intimate symbiosis. 
C)  organism that forms an intimate relationship with another, where both benefit. 
D)  entity composed of multiple types of organisms, including microbes. 
E)  intimate relationship in which one member benefits while harming a host.

Question 18

Culturing methods often detect organisms that may be rare in the environment but prevail when nutrients appear. What are these typically called?

Accepted Answer

A)  weed organisms 
B)  protists 
C)  rhizobia 
D)  OTUs 
E)  microbial dark matter 
A)  weed organisms 
B)  protists 
C)  rhizobia 
D)  OTUs 
E)  microbial dark matter

Question 19

The instrument shown in step 5 of the figure below is used for what metagenomics step?

Accepted Answer

A)  DNA isolation 
B)  DNA sequencing 
C)  sample filtering 
D)  cell lysis 
E)  sequence assembly 
A)  DNA isolation 
B)  DNA sequencing 
C)  sample filtering 
D)  cell lysis 
E)  sequence assembly

Question 20

Explain how endoliths derive energy inside bedrock, where there is no sunlight.

Accepted Answer

Endoliths are chemilithotrophs. It is be

Exam 21: Microbial Ecology

Nonphotosynthetic ________ provide minerals and protection for lichen symbiotic partners.

Which term represents the region of soil influenced by plant roots?

Most forest trees require mycorrhizae for growth because

The ________ region of an oligotrophic lake extends to about 10 meters below the surface.

Eutrophic lakes typically support ten times the microbial concentrations of an oligotrophic lake. Which of the following statements is NOT true of eutrophic lakes?

Compared to eutrophic lakes, the biochemical oxygen demand, or BOD, of oligotrophic lakes is

Name two factors that differentiate aquatic and terrestrial ecosystems and explain how they affect food cycles in these systems.

In the legume-rhizobium symbiosis, nitrogen fixation is carried out in nodules by

Describe the steps in sequencing a metagenome.

The following image illustrates a syntrophic relationship between an archaeon and a bacterium. The technique used to generate this image was

In any environment, pathogens are always outnumbered by a vast community of neutral or helpful microbes. Describe some beneficial as well as devastating incidences of plant pathogens.

How do metatranscriptomics and metaproteomics address functional limitations of metagenomics?

What is coral bleaching? What is its possible cause?

The availability of oxygen and other electron acceptors is the most important determinant of the types of metabolism in a habitat. Which of the following is NOT true about anaerobic environments?

Define BOD, and explain why it can be used to measure the pollution level of lakes. Describe how effluents carrying high levels of nutrients can cause eutrophication.

Compare and contrast the photic zones of freshwater lake and pelagic ecosystems.

A holobiont is defined as an

Culturing methods often detect organisms that may be rare in the environment but prevail when nutrients appear. What are these typically called?

The instrument shown in step 5 of the figure below is used for what metagenomics step?

Explain how endoliths derive energy inside bedrock, where there is no sunlight.

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

Genomes and Chromosomes

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

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

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