Question 1

Resource partitioning would be most likely to occur between

Accepted Answer

A)  sympatric populations of a predator and its prey. 
B)  sympatric populations of species with similar ecological niches. 
C)  sympatric populations of a flowering plant and its specialized insect pollinator. 
D)  allopatric populations of the same animal species. 
E)  allopatric populations of species with similar ecological niches. 
A)  sympatric populations of a predator and its prey. 
B)  sympatric populations of species with similar ecological niches. 
C)  sympatric populations of a flowering plant and its specialized insect pollinator. 
D)  allopatric populations of the same animal species. 
E)  allopatric populations of species with similar ecological niches.

Question 2

According to the nonequilibrium model,

Accepted Answer

A)  community structure remains stable in the absence of interspecific competition. 
B)  communities are assemblages of closely linked species that are irreparably changed by disturbance. 
C)  interspecific interactions induce changes in community composition over time. 
D)  communities are constantly changing after being influenced by disturbances. 
A)  community structure remains stable in the absence of interspecific competition. 
B)  communities are assemblages of closely linked species that are irreparably changed by disturbance. 
C)  interspecific interactions induce changes in community composition over time. 
D)  communities are constantly changing after being influenced by disturbances.

Question 3

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 4

Which of the following is a likely explanation for why invasive species take over communities into which they have been introduced?

Accepted Answer

A)  Invasive species are less efficient than native species in competing for the limited resources of the environment. 
B)  Invasive species are not held in check by the predators and agents of disease that have always been in place for native species. 
C)  Invasive species have a higher reproductive potential than native species. 
D)  Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive. 
A)  Invasive species are less efficient than native species in competing for the limited resources of the environment. 
B)  Invasive species are not held in check by the predators and agents of disease that have always been in place for native species. 
C)  Invasive species have a higher reproductive potential than native species. 
D)  Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive.

Question 5

Imagine five forest communities, each with 100 individuals distributed among four different tree species (W, X, Y, and Z). Which forest community would be most diverse?

Accepted Answer

A)  25W, 25X, 25Y, 25Z 
B)  40W, 30X, 20Y, 10Z 
C)  50W, 25X, 15Y, 10Z 
D)  70W, 10X, 10Y, 10Z 
E)  100W, 0X, 0Y, 0Z 
A)  25W, 25X, 25Y, 25Z 
B)  40W, 30X, 20Y, 10Z 
C)  50W, 25X, 15Y, 10Z 
D)  70W, 10X, 10Y, 10Z 
E)  100W, 0X, 0Y, 0Z

Question 6

The oak tree pathogen Phytophthora ramorum has migrated 800 km in 15 years. West Nile virus spread from New York State to 46 other states in 5 years. The difference in the rate of spread is probably related to

Accepted Answer

A)  the lethality of each pathogen. 
B)  the mobility of their hosts. 
C)  the fact that viruses are very small. 
D)  innate resistance. 
E)  dormancy viability. 
A)  the lethality of each pathogen. 
B)  the mobility of their hosts. 
C)  the fact that viruses are very small. 
D)  innate resistance. 
E)  dormancy viability.

Question 7

Which of the following could qualify as a top-down control on a grassland community?

Accepted Answer

A)  limitation of plant biomass by rainfall amount 
B)  influence of temperature on competition among plants 
C)  influence of soil nutrients on the abundance of grasses versus wildflowers 
D)  effect of grazing intensity by bison on plant species diversity 
A)  limitation of plant biomass by rainfall amount 
B)  influence of temperature on competition among plants 
C)  influence of soil nutrients on the abundance of grasses versus wildflowers 
D)  effect of grazing intensity by bison on plant species diversity

Question 8

Please use the following information to answer the question(s) below.
The symbols +, -, and 0 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 0 denotes an interaction that has no effect on the individuals involved. The first symbol refers to the first organism mentioned.
-What interactions exist between a bee and a flower?

Accepted Answer

A)  +/+ 
B)  +/0 
C)  +/- 
D)  0/0 
E)  -/- 
A)  +/+ 
B)  +/0 
C)  +/- 
D)  0/0 
E)  -/-

Question 9

According to bottom-up and top-down control models of community organization, which of the following expressions would imply that an increase in the size of a carnivore (C) population would negatively impact on its prey (P) population, but not vice versa?

Accepted Answer

A)  P ← C 
B)  P → C 
C)  C ↔ P 
D)  P ← C → P 
E)  C ← P → 
A)  P ← C 
B)  P → C 
C)  C ↔ P 
D)  P ← C → P 
E)  C ← P →

Question 10

Please use the following information to answer the question(s) below.
The symbols +, -, and 0 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 0 denotes an interaction that has no effect on the individuals involved. The first symbol refers to the first organism mentioned.
-What interactions exist between a lion pride and a hyena pack if they utilize the same food sources?

Accepted Answer

A)  +/+ 
B)  +/0 
C)  +/- 
D)  0/0 
E)  -/- 
A)  +/+ 
B)  +/0 
C)  +/- 
D)  0/0 
E)  -/-

Question 11

Please use the following information to answer the question(s) below.
The effect of invasive species on the diversity of communities can be large, and protecting native communities from the invasion of non-native species is often a priority for conservation. You conduct an experiment to study how the impact that invasive plant species have on the diversity of plant communities varies as a function of distance from the source of the invasive species. In this experiment, you create five communities with equal numbers of three native plant species at the beginning. Each of these communities is located at increasing distances from a large patch of an invasive species. You and your research assistant return 1 year later to measure the relative abundance of each species. The results are shown in the table.
Relative Abundance  
-Your research assistant forgets to label the distance at which each community was located. While you wait for your assistant to go back and check on the correct labels, you attempt to match the communities to their distances based on the results. Predict the order of the communities from closest to farthest from the source patch of invasive species.

Accepted Answer

A)  5, 4, 3, 2, 1 
B)  5, 4, 1, 3, 2 
C)  3, 2, 1, 4, 5 
D)  1, 2, 3, 4, 5 
E)  5, 1, 4, 2, 3 
A)  5, 4, 3, 2, 1 
B)  5, 4, 1, 3, 2 
C)  3, 2, 1, 4, 5 
D)  1, 2, 3, 4, 5 
E)  5, 1, 4, 2, 3

Question 12

Which of the following is an example of aposematic coloration?

Accepted Answer

A)  the brightly colored patterns of poison dart frogs 
B)  eye color in humans 
C)  green color of a plant 
D)  colors of an insect-pollinated flower 
E)  a katydid whose wings look like a dead leaf 
A)  the brightly colored patterns of poison dart frogs 
B)  eye color in humans 
C)  green color of a plant 
D)  colors of an insect-pollinated flower 
E)  a katydid whose wings look like a dead leaf

Question 13

Zoonotic disease

Accepted Answer

A)  is caused by suborganismal pathogens such as viruses, viroids, and prions only. 
B)  is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector. 
C)  can only be spread from animals to humans through direct contact. 
D)  can only be transferred from animals to humans by means of an intermediate host. 
E)  is too specific to study at the community level, and studies of zoonotic pathogens are relegated to organismal biology. 
A)  is caused by suborganismal pathogens such as viruses, viroids, and prions only. 
B)  is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector. 
C)  can only be spread from animals to humans through direct contact. 
D)  can only be transferred from animals to humans by means of an intermediate host. 
E)  is too specific to study at the community level, and studies of zoonotic pathogens are relegated to organismal biology.

Question 14

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

Accepted Answer

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

Question 15

How might an ecologist test whether a species is occupying its complete fundamental niche or only a portion of it?

Accepted Answer

A)  Study the temperature range and humidity requirements of the species. 
B)  Observe whether the niche size changes after the addition of nutritional resources to the habitat. 
C)  Observe whether 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)  Observe whether the species expands its range after the removal of a competitor. 
A)  Study the temperature range and humidity requirements of the species. 
B)  Observe whether the niche size changes after the addition of nutritional resources to the habitat. 
C)  Observe whether 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)  Observe whether the species expands its range after the removal of a competitor.

Question 16

Figure 41.2
Examine Figure 41.2. According to the Shannon diversity index, which block shows the greatest diversity?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  5 
A)  1 
B)  2 
C)  3 
D)  4 
E)  5

Question 17

In terms of community ecology, why are pathogens often more virulent now than before?

Accepted Answer

A)  More new pathogens have recently evolved. 
B)  Host organisms have become more susceptible because of weakened immune systems. 
C)  Human activities are transporting pathogens into new habitats (or communities) at an unprecedented rate. 
D)  Medicines for treating pathogenic disease are in short supply. 
E)  Sequencing of genes in pathogenic organisms is particularly difficult. 
A)  More new pathogens have recently evolved. 
B)  Host organisms have become more susceptible because of weakened immune systems. 
C)  Human activities are transporting pathogens into new habitats (or communities) at an unprecedented rate. 
D)  Medicines for treating pathogenic disease are in short supply. 
E)  Sequencing of genes in pathogenic organisms is particularly difficult.

Question 18

According to the competitive exclusion principle, two species cannot continue to occupy the same

Accepted Answer

A)  habitat. 
B)  niche. 
C)  territory. 
D)  range. 
E)  biome. 
A)  habitat. 
B)  niche. 
C)  territory. 
D)  range. 
E)  biome.

Question 19

Figure 41.3
Examine the diagram of a hypothetical food web in Figure 41.3. The arrows represent the transfer of energy between the various trophic levels. Which letter represents an organism that could be a primary producer?

Accepted Answer

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

Question 20

Which of the following best describes resource partitioning?

Accepted Answer

A)  competitive exclusion that results in the success of the superior species 
B)  slight variations in a species' niche that allow similar species to coexist 
C)  two species that can coevolve to share identical niches 
D)  differential resource utilization that results in a decrease in community species diversity 
E)  a climax community that is reached when no new niches are available 
A)  competitive exclusion that results in the success of the superior species 
B)  slight variations in a species' niche that allow similar species to coexist 
C)  two species that can coevolve to share identical niches 
D)  differential resource utilization that results in a decrease in community species diversity 
E)  a climax community that is reached when no new niches are available

Exam 41: Species Interactions

Resource partitioning would be most likely to occur between

According to the nonequilibrium model,

Which statement best describes the evolutionary significance of mutualism?

Which of the following is a likely explanation for why invasive species take over communities into which they have been introduced?

Imagine five forest communities, each with 100 individuals distributed among four different tree species (W, X, Y, and Z). Which forest community would be most diverse?

The oak tree pathogen Phytophthora ramorum has migrated 800 km in 15 years. West Nile virus spread from New York State to 46 other states in 5 years. The difference in the rate of spread is probably related to

Which of the following could qualify as a top-down control on a grassland community?

According to bottom-up and top-down control models of community organization, which of the following expressions would imply that an increase in the size of a carnivore (C) population would negatively impact on its prey (P) population, but not vice versa?

Which of the following is an example of aposematic coloration?

Zoonotic disease

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

How might an ecologist test whether a species is occupying its complete fundamental niche or only a portion of it?

Figure 41.2 Examine Figure 41.2. According to the Shannon diversity index, which block shows the greatest diversity?

In terms of community ecology, why are pathogens often more virulent now than before?

According to the competitive exclusion principle, two species cannot continue to occupy the same

Figure 41.3 Examine the diagram of a hypothetical food web in Figure 41.3. The arrows represent the transfer of energy between the various trophic levels. Which letter represents an organism that could be a primary producer?

Which of the following best describes resource partitioning?

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Ecosystems and Energy

Global Ecology and Conservation Biology

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