Question 1

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

Accepted Answer

A) True 
 B)False

Question 2

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)   bacteriaE) A) and D)
F) C) and D)

Question 3

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.E) B) and C)
F) C) and D)

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 bacterium Thiobacillus secretes sulfuric acid into the environment.

Accepted Answer

A) True 
 B)False  True

Question 6

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)   communityF) A) and B)
G) D) and E)

Question 7

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.E) A) and D)
F) A) and C) A

Question 8

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

Accepted Answer

A) True 
 B)False

Question 9

There are very few viruses in aquatic environments.

Accepted Answer

A) True 
 B)False

Question 10

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)   biomeF) B) and C)
G) D) and E)

Question 11

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.E) B) and C)
F) A) and B)

Question 12

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

Accepted Answer

A) True 
 B)False

Question 13

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.F) A) and D)
G) A) and B)

Question 14

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

Accepted Answer

A)   saprobism
B)   decomposition
C)   mineralization
D)   bioremediation
E)   parasitismF) All of the above
G) B) and C)

Question 15

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

Accepted Answer

A)   oligotrophic
B)   thermophilic
C)   anaerobic
D)   autotrophicE) C) and D)
F) A) and B)

Question 16

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.E) None of the above
F) B) and C)

Question 17

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

Accepted Answer

A)   decomposers
B)   saprophytes
C)   lithotrophs
D)   autotrophs
E)   consumersF) All of the above
G) B) and E)

Question 18

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 consumersF) A) and C)
G) B) and E)

Question 19

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.F) A) and B)
G) C) and D) E

Question 20

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

Accepted Answer

A)   nitrogen ﬁxation
B)   nitriﬁcation
C)   denitriﬁcation
D)   photosynthesis
E)   ammoniﬁcationF) A) and B)
G) B) and E)

Exam 24: Microbes and the Environment

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

The bacterium Thiobacillus secretes sulfuric acid into the environment.

Correct Answer
verified
True

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

Correct Answer
verified

How are the sulfur cycle and the phosphate cycle interconnected?

Correct Answer
verified
A

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

Correct Answer
verified

There are very few viruses in aquatic environments.

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

Eutrophication _______.

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

Which of the following statements concerning metagenomic sequencing is incorrect?

Correct Answer
verified

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

Correct Answer
verified

Which trophic level forms the base of a food chain?

Correct Answer
verified

Carbon dioxide (CO₂) is _______.

Correct Answer
verified
E

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

Correct Answer
verified

Exam 24: Microbes and the Environment

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

The bacterium Thiobacillus secretes sulfuric acid into the environment.

Correct AnswerverifiedTrue

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

Correct AnswerverifiedShow Answer

How are the sulfur cycle and the phosphate cycle interconnected?

Correct AnswerverifiedA

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

Correct AnswerverifiedShow Answer

There are very few viruses in aquatic environments.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Eutrophication _______.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which of the following statements concerning metagenomic sequencing is incorrect?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Which trophic level forms the base of a food chain?

Correct AnswerverifiedShow Answer

Carbon dioxide (CO₂) is _______.

Correct AnswerverifiedE

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

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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True

Correct Answer
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Correct Answer
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A

Correct Answer
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Correct Answer
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Correct Answer
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E

Correct Answer
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