Question 1

Which statement best describes the evolutionary significance of mutualism?

Accepted Answer

A) Mutualism offers more biodiversity to a community. 
B) Individuals partaking in a mutualistic relationship are more resistant to parasites. 
C) Interaction increases the survival and reproductive rates of mutualistic species. 
D) Mutualistic interaction lessens competition in communities where it is present. 
E) Mutualistic relationships allow organisms to synthesize and use energy more efficiently. 
A) Mutualism offers more biodiversity to a community. 
B) Individuals partaking in a mutualistic relationship are more resistant to parasites. 
C) Interaction increases the survival and reproductive rates of mutualistic species. 
D) Mutualistic interaction lessens competition in communities where it is present. 
E) Mutualistic relationships allow organisms to synthesize and use energy more efficiently.

Question 2

How might an ecologist test whether a species is occupying its realized or its fundamental niche?

Accepted Answer

A) Study the temperature range and humidity requirements of the species. 
B) Observe if the niche size changes after the addition of nutritional resources to the habitat. 
C) Observe if the niche size changes after the introduction of a similar non-native species. 
D) Measure the change in reproductive success when the species is subjected to environmental stress. 
E) Remove a competitor species to see if the species expands its range. 
A) Study the temperature range and humidity requirements of the species. 
B) Observe if the niche size changes after the addition of nutritional resources to the habitat. 
C) Observe if the niche size changes after the introduction of a similar non-native species. 
D) Measure the change in reproductive success when the species is subjected to environmental stress. 
E) Remove a competitor species to see if the species expands its range.

Question 3

Why is a pathogen generally more virulent in a new habitat?

Accepted Answer

A) More pathogens tend to immigrate into newer habitats. 
B) Intermediate host species are more motile and transport pathogens to new areas. 
C) Pathogens evolve more efficient forms of reproduction in new environments. 
D) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection. 
E) New environments are almost always smaller in area so that transmission of pathogens is easily accomplished between hosts. 
A) More pathogens tend to immigrate into newer habitats. 
B) Intermediate host species are more motile and transport pathogens to new areas. 
C) Pathogens evolve more efficient forms of reproduction in new environments. 
D) Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection. 
E) New environments are almost always smaller in area so that transmission of pathogens is easily accomplished between hosts.

Question 4

There are more species in tropical areas than in places more distant from the equator.This is probably a result of

Accepted Answer

A) fewer predators. 
B) more intense annual solar radiation. 
C) more frequent ecological disturbances. 
D) fewer agents of disease. 
E) fewer predators, more intense annual solar radiation, more frequent ecological disturbances, and fewer agents of disease. 
A) fewer predators. 
B) more intense annual solar radiation. 
C) more frequent ecological disturbances. 
D) fewer agents of disease. 
E) fewer predators, more intense annual solar radiation, more frequent ecological disturbances, and fewer agents of disease.

Question 5

Which of the following terms is used by ecologists to describe the community interaction where one organism makes the environment more suitable for another organism?

Accepted Answer

A) parasitism 
B) mutualism 
C) inhibition 
D) facilitation 
E) commensalism 
A) parasitism 
B) mutualism 
C) inhibition 
D) facilitation 
E) commensalism

Question 6

Many zootonic pathogens are highly virulent,can result in high death rates,and can cause world-wide pandemics.One example,the H5N1 avian flu,not only killed millions of domestic poultry,but also caused the deaths of people who came in contact with sick birds.What is the most probable hypothesis or reason as to why the H5N1 flu can be so deadly to people?

Accepted Answer

A) This particular pathogen crossed the species barrier and the high virulence can be seen as a side effect of a new pathogen-host association. 
B) The pathogen was quick to infect healthy birds. 
C) The avian flu would have eventually been controlled; we have to be patient because medicine is close to eliminating infectious diseases. 
D) If the H5N1 flu had been half avian and half mammalian, people would have had some immunity to it. 
E) Two of the above statements are correct. 
A) This particular pathogen crossed the species barrier and the high virulence can be seen as a side effect of a new pathogen-host association. 
B) The pathogen was quick to infect healthy birds. 
C) The avian flu would have eventually been controlled; we have to be patient because medicine is close to eliminating infectious diseases. 
D) If the H5N1 flu had been half avian and half mammalian, people would have had some immunity to it. 
E) Two of the above statements are correct.

Question 7

The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that

Accepted Answer

A) tropical communities are younger. 
B) tropical regions generally have more available water and higher levels of solar radiation. 
C) higher temperatures cause more rapid speciation. 
D) diversity increases as evapotranspiration decreases. 
E) tropical regions have very high rates of immigration and very low rates of extinction. 
A) tropical communities are younger. 
B) tropical regions generally have more available water and higher levels of solar radiation. 
C) higher temperatures cause more rapid speciation. 
D) diversity increases as evapotranspiration decreases. 
E) tropical regions have very high rates of immigration and very low rates of extinction.

Question 8

Which term do ecologists use to describe the ability of a community either to resist change or to recover to its original state after change?

Accepted Answer

A) stability 
B) succession 
C) partitioning 
D) productivity 
E) competitive exclusion 
A) stability 
B) succession 
C) partitioning 
D) productivity 
E) competitive exclusion

Question 9

The energetic hypothesis and dynamic stability hypothesis are ideas that attempt to explain

Accepted Answer

A) plant defences against herbivores. 
B) the length of food chains. 
C) the evolution of mutualism. 
D) resource partitioning. 
E) competitive exclusion. 
A) plant defences against herbivores. 
B) the length of food chains. 
C) the evolution of mutualism. 
D) resource partitioning. 
E) competitive exclusion.

Question 10

In a tide pool,15 species of invertebrates were reduced to eight after one species was removed.The species removed was likely a(n)

Accepted Answer

A) pathogen. 
B) keystone species. 
C) herbivore. 
D) resource partitioner. 
E) mutualistic organism. 
A) pathogen. 
B) keystone species. 
C) herbivore. 
D) resource partitioner. 
E) mutualistic organism.

Question 11

The symbols +,-,and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow.The symbol + denotes a positive interaction,- denotes a negative interaction,and o denotes where individuals are not affected by interacting.The first symbol refers to the first organism mentioned.
-What interactions exist between a "carrier crab" and "sea urchin hitch-hiker"?

Accepted Answer

A) +/+ 
B) +/o 
C) +/- 
D) o/o 
E) -/- 
A) +/+ 
B) +/o 
C) +/- 
D) o/o 
E) -/-

Question 12

The Ebola virus is a very virulent zootonic pathogen that causes high mortality rates among people.In humans,this virus causes Ebola hemorrhagic fever (severe internal bleeding)and,in some years,mortality can reach 100%.The virus is likely transmitted from wild animals to people and spreads via human to human transmission.There is no vaccine or cure for people.If the virus is so deadly and kills its human hosts,speculate on a possible reason why the virus continues to survive and has not died off with the human hosts it kills in such large numbers.

Accepted Answer

A) The virus lays dormant until another human host comes along. 
B) The Ebola virus is most likely related to other rare human viruses. 
C) The virus can kill people without becoming extinct because it survives in its natural host. 
D) The virus can exchange genes with other viruses and stay alive. 
E) The Ebola virus is in low numbers now, but once people acquire an immunity to it, then the virus will recover. 
A) The virus lays dormant until another human host comes along. 
B) The Ebola virus is most likely related to other rare human viruses. 
C) The virus can kill people without becoming extinct because it survives in its natural host. 
D) The virus can exchange genes with other viruses and stay alive. 
E) The Ebola virus is in low numbers now, but once people acquire an immunity to it, then the virus will recover.

Question 13

Use the following diagram of five islands formed at around the same time near a particular mainland,as well as MacArthur and Wilson's island biogeography principles,to answer the following questions.
  
-Which island would likely have the greatest species diversity?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) E 
A) A 
B) B 
C) C 
D) D 
E) E

Question 14

The symbols +,-,and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow.The symbol + denotes a positive interaction,- denotes a negative interaction,and o denotes where individuals are not affected by interacting.The first symbol refers to the first organism mentioned.
-What interactions exist between mycorrhizae and evergreen tree roots?

Accepted Answer

A) +/+ 
B) +/o 
C) +/- 
D) o/o 
E) -/- 
A) +/+ 
B) +/o 
C) +/- 
D) o/o 
E) -/-

Question 15

How did Eugene Odum describe an ecological niche?

Accepted Answer

A) the "address" of an organism 
B) an entity that is synonymous with an organism's specific trophic level 
C) an organism's "profession" in the community 
D) the organism's role in recycling nutrients in its habitat 
E) the interactions of the organism with other members of the community 
A) the "address" of an organism 
B) an entity that is synonymous with an organism's specific trophic level 
C) an organism's "profession" in the community 
D) the organism's role in recycling nutrients in its habitat 
E) the interactions of the organism with other members of the community

Question 16

Which of the following studies would shed light on the mechanism of spread of H5N1 from Asia?

Accepted Answer

A) Perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska. 
B) Test fecal samples for H5N1 in Asian waterfowl that live near domestic poultry farms in Asia. 
C) Test for the presence of H5N1 in poultry used for human consumption worldwide. 
D) Locate and destroy birds infected with H5N1 in Asian open-air poultry markets. 
E) Keep domestic and wild fowl from interacting with each other to minimize the probability that wild fowl could get infected and migrate out of Asia. 
A) Perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska. 
B) Test fecal samples for H5N1 in Asian waterfowl that live near domestic poultry farms in Asia. 
C) Test for the presence of H5N1 in poultry used for human consumption worldwide. 
D) Locate and destroy birds infected with H5N1 in Asian open-air poultry markets. 
E) Keep domestic and wild fowl from interacting with each other to minimize the probability that wild fowl could get infected and migrate out of Asia.

Question 17

Use the following diagram of a hypothetical food web to answer the following questions.The arrows represent the transfer of food energy between the various trophic levels.
  
-Which letter represents an organism that could be a primary consumer?

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) E 
A) A 
B) B 
C) C 
D) D 
E) E

Question 18

In the hypothesis that C.stellatus (a species of barnacle)is competitively excluded from the lower intertidal zone by B.balanoides (another species of barnacle),what could be concluded about the two species?

Accepted Answer

A) The fundamental and realized niches of B. balanoides and C. stellatus are identical. 
B) The fundamental and realized niches of B. balanoides and C. stellatus are different. 
C) The fundamental and realized niches of B. balanoides are different, but the fundamental and realized niches of C. stellatus are identical. 
D) The fundamental and realized niches of B. balanoides are identical, but the fundamental and realized niches of C. stellatus are different. 
A) The fundamental and realized niches of B. balanoides and C. stellatus are identical. 
B) The fundamental and realized niches of B. balanoides and C. stellatus are different. 
C) The fundamental and realized niches of B. balanoides are different, but the fundamental and realized niches of C. stellatus are identical. 
D) The fundamental and realized niches of B. balanoides are identical, but the fundamental and realized niches of C. stellatus are different.

Question 19

An event that changes resource availability and removes individuals from a community is a

Accepted Answer

A) predator effect. 
B) competitor effect. 
C) disturbance. 
D) disease. 
E) disaster. 
A) predator effect. 
B) competitor effect. 
C) disturbance. 
D) disease. 
E) disaster.

Question 20

Which of the following studies would a community ecologist undertake to learn about competitive interactions?
I. selectivity of nest sites among cavity-nesting songbirds
II. the grass species preferred by grazing pronghorn antelope and bison
III.stomach analysis of brown trout and brook trout in streams where they coexist

Accepted Answer

A) only I and II 
B) only I and III 
C) only II and III 
D) I, II, and III 
A) only I and II 
B) only I and III 
C) only II and III 
D) I, II, and III

Exam 54: Community Ecology

Which statement best describes the evolutionary significance of mutualism?

How might an ecologist test whether a species is occupying its realized or its fundamental niche?

Why is a pathogen generally more virulent in a new habitat?

There are more species in tropical areas than in places more distant from the equator.This is probably a result of

Which of the following terms is used by ecologists to describe the community interaction where one organism makes the environment more suitable for another organism?

The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that

Which term do ecologists use to describe the ability of a community either to resist change or to recover to its original state after change?

The energetic hypothesis and dynamic stability hypothesis are ideas that attempt to explain

In a tide pool,15 species of invertebrates were reduced to eight after one species was removed.The species removed was likely a(n)

Use the following diagram of five islands formed at around the same time near a particular mainland,as well as MacArthur and Wilson's island biogeography principles,to answer the following questions. -Which island would likely have the greatest species diversity?

How did Eugene Odum describe an ecological niche?

Which of the following studies would shed light on the mechanism of spread of H5N1 from Asia?

Use the following diagram of a hypothetical food web to answer the following questions.The arrows represent the transfer of food energy between the various trophic levels. -Which letter represents an organism that could be a primary consumer?

In the hypothesis that C.stellatus (a species of barnacle)is competitively excluded from the lower intertidal zone by B.balanoides (another species of barnacle),what could be concluded about the two species?

An event that changes resource availability and removes individuals from a community is a

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure,Growth,and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons,Synapses,and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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