Question 1

The bacterium Thiobacillus secretes sulfuric acid into the environment.

Accepted Answer

A) True 
 B)False  True

Question 2

Carbon dioxide (CO₂) is _______.

Accepted Answer

A)  removed from the atmosphere during photosynthesis 
B)  a source of carbon for autotrophs 
C)  returned to the atmosphere during respiration and fermentation 
D)  used by marine organisms to make limestone for their hard shells 
E)  All of the choices are correct. 
A)  removed from the atmosphere during photosynthesis 
B)  a source of carbon for autotrophs 
C)  returned to the atmosphere during respiration and fermentation 
D)  used by marine organisms to make limestone for their hard shells 
E)  All of the choices are correct. E

Question 3

How are the sulfur cycle and the phosphate cycle interconnected?

Accepted Answer

A)  Phosphate is released from rock and soil by sulfuric acid. 
B)  Sulfate and phosphate react together to produce amino acids for protein production. 
C)  Sulﬁte is the nutrient used by phosphate reducers. 
D)  Phosphate is the nutrient source used by sulfur oxidizers. 
A)  Phosphate is released from rock and soil by sulfuric acid. 
B)  Sulfate and phosphate react together to produce amino acids for protein production. 
C)  Sulﬁte is the nutrient used by phosphate reducers. 
D)  Phosphate is the nutrient source used by sulfur oxidizers. A

Question 4

The total amount of water in the hydrologic cycle has been decreasing over the last million years.

Accepted Answer

A) True 
 B)False

Question 5

The conversion of gaseous nitrogen (N2) to ammonia (NH₄+) occurs during ______.

Accepted Answer

A)  nitrogen ﬁxation 
B)  nitriﬁcation 
C)  denitriﬁcation 
D)  photosynthesis 
E)  ammoniﬁcation 
A)  nitrogen ﬁxation 
B)  nitriﬁcation 
C)  denitriﬁcation 
D)  photosynthesis 
E)  ammoniﬁcation

Question 6

Which of the following statements concerning metagenomic sequencing is incorrect?

Accepted Answer

A)  The samples are subject to polymerase chain reaction for ampliﬁcation. 
B)  The sequences of the ampliﬁed fragments are determined by next-generation methods. 
C)  Software aligns sequences and assemble large portions of genomes. 
D)  Proteins are extracted from an environment, fragmented, and adaptors are added. 
A)  The samples are subject to polymerase chain reaction for ampliﬁcation. 
B)  The sequences of the ampliﬁed fragments are determined by next-generation methods. 
C)  Software aligns sequences and assemble large portions of genomes. 
D)  Proteins are extracted from an environment, fragmented, and adaptors are added.

Question 7

There are very few viruses in aquatic environments.

Accepted Answer

A) True 
 B)False

Question 8

Consider a deep sea hydrothermal vent. Which of the following statements is incorrect?

Accepted Answer

A)  Its biome is the deep marine biopshere. 
B)  The vent hosts communities of chemolithotrophic bacteria. 
C)  The vent is a habitat. 
D)  The associated chemolithotrophs are primary producers. 
A)  Its biome is the deep marine biopshere. 
B)  The vent hosts communities of chemolithotrophic bacteria. 
C)  The vent is a habitat. 
D)  The associated chemolithotrophs are primary producers.

Question 9

Organisms whose sole source of carbon for growth is CO₂ are called ______.

Accepted Answer

A)  decomposers 
B)  saprophytes 
C)  lithotrophs 
D)  autotrophs 
E)  consumers 
A)  decomposers 
B)  saprophytes 
C)  lithotrophs 
D)  autotrophs 
E)  consumers

Question 10

The major group of organisms that ﬁx nitrogen into ammonia and then oxidize it to nitrate are ______.

Accepted Answer

A)  protozoa 
B)  algae 
C)  fungi 
D)  bacteria 
A)  protozoa 
B)  algae 
C)  fungi 
D)  bacteria

Question 11

Living or dead organisms that occupy an organism's habitat are called biotic factors.

Accepted Answer

A) True 
 B)False

Question 12

You are "living off the grid" meaning that you are not using any public utilities: no water supply, sewer connection, natural gas, or electricity. You do have a septic tank, whose pipe carries sewage underground where it is released over a wide area, the leaching ?eld. There is also a small pond out there that you have stocked with ?sh. However, you notice that the ?sh are ?oating dead in the water, and the pond has a green scum on it. What happened?

Accepted Answer

A)  Chemical toxins from your septic tank cleaner have killed the ?sh. 
B)  There are not enough nutrients in the water, so the ?sh died. 
C)  The ?sh died due to a lack of calcium, which then caused the algae to overgrow. 
D)  There is oxygen depletion in the pond due to the leakage of phosphates and other compounds from your septic tank. 
A)  Chemical toxins from your septic tank cleaner have killed the ?sh. 
B)  There are not enough nutrients in the water, so the ?sh died. 
C)  The ?sh died due to a lack of calcium, which then caused the algae to overgrow. 
D)  There is oxygen depletion in the pond due to the leakage of phosphates and other compounds from your septic tank.

Question 13

Methane is a signi?cant part of the carbon cycle in ______ environments dominated by methanogens.

Accepted Answer

A)  oligotrophic 
B)  thermophilic 
C)  anaerobic 
D)  autotrophic 
A)  oligotrophic 
B)  thermophilic 
C)  anaerobic 
D)  autotrophic

Question 14

The primary role of producers is the recycling of nutrients in an ecosystem.

Accepted Answer

A) True 
 B)False

Question 15

Which trophic level forms the base of a food chain?

Accepted Answer

A)  Secondary consumers 
B)  Tertiary consumers 
C)  Primary producers 
D)  Primary consumers 
E)  Quaternary consumers 
A)  Secondary consumers 
B)  Tertiary consumers 
C)  Primary producers 
D)  Primary consumers 
E)  Quaternary consumers

Question 16

Metagenomic analysis involves DNA sequencing of various samples taken from a particular habitat.

Accepted Answer

A) True 
 B)False

Question 17

The physical location in the environment to which an organism has adapted is its ______.

Accepted Answer

A)  habitat 
B)  niche 
C)  population 
D)  community 
E)  biome 
A)  habitat 
B)  niche 
C)  population 
D)  community 
E)  biome

Question 18

A group of organisms of the same genus within a community is called a ______.

Accepted Answer

A)  biome 
B)  population 
C)  niche 
D)  habitat 
E)  community 
A)  biome 
B)  population 
C)  niche 
D)  habitat 
E)  community

Question 19

Eutrophication _______.

Accepted Answer

A)  is characterized by heavy surface algal blooms 
B)  restricts the O₂ supply to water below the surface 
C)  occurs when there are excess nutrients in aquatic ecosystems 
D)  causes massive die-off of ﬁsh and invertebrates 
E)  All of the choices are correct. 
A)  is characterized by heavy surface algal blooms 
B)  restricts the O₂ supply to water below the surface 
C)  occurs when there are excess nutrients in aquatic ecosystems 
D)  causes massive die-off of ﬁsh and invertebrates 
E)  All of the choices are correct.

Question 20

The breakdown of man-made compounds by decomposers is called ______.

Accepted Answer

A)  saprobism 
B)  decomposition 
C)  mineralization 
D)  bioremediation 
E)  parasitism 
A)  saprobism 
B)  decomposition 
C)  mineralization 
D)  bioremediation 
E)  parasitism

Exam 24: Microbes and the Environment

The bacterium Thiobacillus secretes sulfuric acid into the environment.

Carbon dioxide (CO₂) is _______.

How are the sulfur cycle and the phosphate cycle interconnected?

The total amount of water in the hydrologic cycle has been decreasing over the last million years.

The conversion of gaseous nitrogen (N2) to ammonia (NH₄+) occurs during ______.

Which of the following statements concerning metagenomic sequencing is incorrect?

There are very few viruses in aquatic environments.

Consider a deep sea hydrothermal vent. Which of the following statements is incorrect?

Organisms whose sole source of carbon for growth is CO₂ are called ______.

The major group of organisms that ﬁx nitrogen into ammonia and then oxidize it to nitrate are ______.

Living or dead organisms that occupy an organism's habitat are called biotic factors.

Methane is a signi?cant part of the carbon cycle in ______ environments dominated by methanogens.

The primary role of producers is the recycling of nutrients in an ecosystem.

Which trophic level forms the base of a food chain?

Metagenomic analysis involves DNA sequencing of various samples taken from a particular habitat.

The physical location in the environment to which an organism has adapted is its ______.

A group of organisms of the same genus within a community is called a ______.

Eutrophication _______.

The breakdown of man-made compounds by decomposers is called ______.

The Main Themes of Microbiology

The Chemistry of Biology

Tools of the Laboratory: Methods for the Culturing of Microscopic Analysis of Microorganisms

Bacteria and Archaea

Eukaryotic Cells and Microorganisms

Viruses and Prions

Microbial Nutrition and Growth

Microbial Metabolism: the Chemical Crossroads of Life

Microbial Genetics

Genetic Analysis and Genetic Engineering

Physical and Chemical Control of Microbes

Antimicrobial Treatment

Microbe-Human Interactions: Health and Disease

Host Defenses I: Overview and Nonspecific Defenses

Host Defenses Ii: Specific Immunity and Immunization

Disorders in Immunity

Diagnosing Infections

Infectious Diseases Affecting the Skin and Eyes

Infectious Diseases Affecting the Nervous System

Infectious Diseases Affecting the Cardiovascular and Lymphatic Systems

Infectious Diseases Affecting the Respiratory System

Infectious Diseases Affecting the Gastrointestinal Tract

Infectious Diseases Affecting the Genitourinary System

Applied Microbiology and Food and Water Safety

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