Question 1

In the marine photic zone, the rate of photosynthesis

Accepted Answer

A)  is equal to the amount of CO₂ released from the niche. 
B)  exceeds the rate of respiration. 
C)  is less than the respiration rate. 
D)  does not affect carbon cycling. 
E)  is inversely related to rate of respiration. 
A)  is equal to the amount of CO₂ released from the niche. 
B)  exceeds the rate of respiration. 
C)  is less than the respiration rate. 
D)  does not affect carbon cycling. 
E)  is inversely related to rate of respiration.

Question 2

Which of the following would decrease the amount of carbon dioxide in the atmosphere?

Accepted Answer

A)  burning of logs 
B)  microbial decomposition of logs 
C)  increase in photosynthesis by plants 
D)  anaerobic fermentation 
E)  increase in respiration by microbes 
A)  burning of logs 
B)  microbial decomposition of logs 
C)  increase in photosynthesis by plants 
D)  anaerobic fermentation 
E)  increase in respiration by microbes

Question 3

Which of the following is NOT an example of a reduced form of carbon in the carbon cycle?

Accepted Answer

A)  methane 
B)  biomass 
C)  hydrocarbons 
D)  carbon dioxide 
E)  methanol 
A)  methane 
B)  biomass 
C)  hydrocarbons 
D)  carbon dioxide 
E)  methanol

Question 4

Which of the following is NOT used as a biosignature?

Accepted Answer

A)  metabolic activity 
B)  isotope ratios 
C)  microscopic imaging 
D)  mineral formations 
E)  microfossils 
A)  metabolic activity 
B)  isotope ratios 
C)  microscopic imaging 
D)  mineral formations 
E)  microfossils

Question 5

Compare and contrast assimilatory and dissimilatory nitrate reduction.

Accepted Answer

Nitrate assimilation to biomass (NH₄⁺) i

Question 6

What types of evidence suggest the past existence of water on Mars?

Accepted Answer

Martian soil composition showed high lev

Question 7

Which of the following major biological elements has the highest number of oxidation states?

Accepted Answer

A)  nitrogen 
B)  carbon 
C)  hydrogen 
D)  sulfur 
E)  oxygen 
A)  nitrogen 
B)  carbon 
C)  hydrogen 
D)  sulfur 
E)  oxygen

Question 8

Which of these is involved in commercial chemical fertilizer production?

Accepted Answer

A)  lightning strikes 
B)  the Haber process 
C)  cellular nitrogen fixation 
D)  nitrification 
E)  denitrification 
A)  lightning strikes 
B)  the Haber process 
C)  cellular nitrogen fixation 
D)  nitrification 
E)  denitrification

Question 9

Wastewater treatment generates which of the following gases in quantities sufficient for recovery as fuel?

Accepted Answer

A)  carbon dioxide 
B)  oxygen 
C)  nitrous oxide 
D)  methane 
E)  hydrogen sulfide 
A)  carbon dioxide 
B)  oxygen 
C)  nitrous oxide 
D)  methane 
E)  hydrogen sulfide

Question 10

Discuss how human activities have perturbed the nitrogen cycle.

Accepted Answer

Dinitrogen gas constitutes about 79% of

Question 11

Which of the following techniques is used to quantify carbon influx and efflux of CO₂ in small, controlled model ecosystems?

Accepted Answer

A)  gas chromatography 
B)  mass spectroscopy 
C)  radioisotope incorporation 
D)  stable isotope ratios 
E)  atomic force microscopy 
A)  gas chromatography 
B)  mass spectroscopy 
C)  radioisotope incorporation 
D)  stable isotope ratios 
E)  atomic force microscopy

Question 12

Aeration of an environment containing microbes actively producing methane will

Accepted Answer

A)  increase methane release. 
B)  decrease methane release. 
C)  not affect methane release. 
D)  increase nitrous oxide release. 
E)  increase dinitrogen release. 
A)  increase methane release. 
B)  decrease methane release. 
C)  not affect methane release. 
D)  increase nitrous oxide release. 
E)  increase dinitrogen release.

Question 13

Corrosion of cement in the sewer pipe shown below is caused by

Accepted Answer

A)  H₂S. 
B)  H₂S + O₂. 
C)  H₂ + SO₄2-. 
D)  Ca(OH)₂ + H₂SO₄. 
E)  sewage liquid. 
A)  H₂S. 
B)  H₂S + O₂. 
C)  H₂ + SO₄2-. 
D)  Ca(OH)₂ + H₂SO₄. 
E)  sewage liquid.

Question 14

Which is the most stable form of nitrogen?

Accepted Answer

A)  NO 
B)  NO₂- 
C)  N₂ 
D)  NH3 
E)  NH 
A)  NO 
B)  NO₂- 
C)  N₂ 
D)  NH3 
E)  NH

Question 15

The release of CO₂ by human industry has/is ________ the rate of CO₂ fixation globally.

Accepted Answer

A)  equal to 
B)  tripled 
C)  outpaced 
D)  far less than 
E)  decreased 
A)  equal to 
B)  tripled 
C)  outpaced 
D)  far less than 
E)  decreased

Question 16

If life is found on other planets, it will almost certainly be

Accepted Answer

A)  thermophilic. 
B)  microbial. 
C)  barophilic. 
D)  psychrophilic. 
E)  multicellular. 
A)  thermophilic. 
B)  microbial. 
C)  barophilic. 
D)  psychrophilic. 
E)  multicellular.

Question 17

Some bacteria are responsible for degrading concrete. How do they accomplish this?

Accepted Answer

In a concrete sewer pipe, the alternatio

Question 18

The Blood Falls ecosystem is driven by microbes that reduce ________ and others that oxidize ________.

Accepted Answer

A)  nitrogen; iron 
B)  phosphorus; nitrogen 
C)  iron; sulfur 
D)  sulfur; nitrogen 
E)  carbon; sulfur 
A)  nitrogen; iron 
B)  phosphorus; nitrogen 
C)  iron; sulfur 
D)  sulfur; nitrogen 
E)  carbon; sulfur

Question 19

The sink of an element in the ecosystem

Accepted Answer

A)  is the reservoir to which it returns during cycling. 
B)  is the most accessible reservoir of that element. 
C)  renders the element inaccessible. 
D)  releases the element into the subsurface. 
E)  is the source of the element for living organisms. 
A)  is the reservoir to which it returns during cycling. 
B)  is the most accessible reservoir of that element. 
C)  renders the element inaccessible. 
D)  releases the element into the subsurface. 
E)  is the source of the element for living organisms.

Question 20

Compare and contrast carbon cycling in aerobic versus anaerobic terrestrial systems.

Accepted Answer

Answers may vary. Although plants perfor

Exam 22: Microbes in Global Elemental Cycles

In the marine photic zone, the rate of photosynthesis

Which of the following would decrease the amount of carbon dioxide in the atmosphere?

Which of the following is NOT an example of a reduced form of carbon in the carbon cycle?

Which of the following is NOT used as a biosignature?

Compare and contrast assimilatory and dissimilatory nitrate reduction.

What types of evidence suggest the past existence of water on Mars?

Which of the following major biological elements has the highest number of oxidation states?

Which of these is involved in commercial chemical fertilizer production?

Wastewater treatment generates which of the following gases in quantities sufficient for recovery as fuel?

Discuss how human activities have perturbed the nitrogen cycle.

Which of the following techniques is used to quantify carbon influx and efflux of CO₂ in small, controlled model ecosystems?

Aeration of an environment containing microbes actively producing methane will

Corrosion of cement in the sewer pipe shown below is caused by

Which is the most stable form of nitrogen?

The release of CO₂ by human industry has/is ________ the rate of CO₂ fixation globally.

If life is found on other planets, it will almost certainly be

Some bacteria are responsible for degrading concrete. How do they accomplish this?

The Blood Falls ecosystem is driven by microbes that reduce ________ and others that oxidize ________.

The sink of an element in the ecosystem

Compare and contrast carbon cycling in aerobic versus anaerobic terrestrial systems.

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

Microbial Ecology

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters

The Blood Falls ecosystem is driven by microbes that reduce and others that oxidize .