Question 1

Define the two key pieces of information used to examine diversity within a community.

Accepted Answer

Both relative species abundance, a comparison of how common species are, and species richness, the total number of species within the community, characterize the diversity within a given community.

Question 2

Which of the following communities would be considered to have the greatest species richness?

Accepted Answer

A) An elk gut with 240 species of microorganisms where 95 percent of the microorganisms are bacteria. 
B) A small forest in North America made up of 10 species of birds, 125 insect species, and five tree species. 
C) A community of 150 small invertebrates classified as 15 different species living within a puddle. 
D) A large grassland community in South America with 175 species of grasses, birds, and insects. 
A) An elk gut with 240 species of microorganisms where 95 percent of the microorganisms are bacteria. 
B) A small forest in North America made up of 10 species of birds, 125 insect species, and five tree species. 
C) A community of 150 small invertebrates classified as 15 different species living within a puddle. 
D) A large grassland community in South America with 175 species of grasses, birds, and insects. A

Question 3

How do ecological communities change over time?

Accepted Answer

A) Interactions between and among species may cause changes in ecological communities over time. 
B) Keystone species typically become the most common species within an ecological community. 
C) Species richness typically declines as one species outcompetes all other species. 
D) Ecological communities are defined at a given point in time; any change leads to re-classification of the community. 
A) Interactions between and among species may cause changes in ecological communities over time. 
B) Keystone species typically become the most common species within an ecological community. 
C) Species richness typically declines as one species outcompetes all other species. 
D) Ecological communities are defined at a given point in time; any change leads to re-classification of the community. A

Question 4

Which of the following would probably NOT occur if a single species was removed from an ecological community?

Accepted Answer

A) The species richness would change. 
B) The relative species abundance would change. 
C) The diversity of the community would change. 
D) The community would cease to exist. 
A) The species richness would change. 
B) The relative species abundance would change. 
C) The diversity of the community would change. 
D) The community would cease to exist.

Question 5

After studying the food web shown, select a reasonable outcome following the complete disappearance of wolves.

Accepted Answer

A) Coyotes may decline because they eat wolves. 
B) Coyotes may increase because one of their primary predators is gone. 
C) Grass, willow, and berries will increase as more elk become available. 
D) Voles may decline as coyotes become less abundant. 
A) Coyotes may decline because they eat wolves. 
B) Coyotes may increase because one of their primary predators is gone. 
C) Grass, willow, and berries will increase as more elk become available. 
D) Voles may decline as coyotes become less abundant.

Question 6

Can a human being be considered an ecological community?

Accepted Answer

A) Yes, for example, a community of microorganisms lives within the human digestive system. 
B) Yes, human beings live with other humans, own pets, and grow domesticated crops. 
C) No, a community is formed from many populations, and it takes more than one individual to make up a population. 
D) No, human populations are artificial rather than natural and are considered to fall outside of ecology. 
A) Yes, for example, a community of microorganisms lives within the human digestive system. 
B) Yes, human beings live with other humans, own pets, and grow domesticated crops. 
C) No, a community is formed from many populations, and it takes more than one individual to make up a population. 
D) No, human populations are artificial rather than natural and are considered to fall outside of ecology.

Question 7

Which of the following statements accurately describes an ecological community?

Accepted Answer

A) Communities have clearly fixed boundaries and are always defined on the same scale. 
B) Communities can be nested within a larger one. 
C) Communities are defined as groups of four or more species within a given area. 
D) Communities are groups of species that do not fluctuate over time. 
A) Communities have clearly fixed boundaries and are always defined on the same scale. 
B) Communities can be nested within a larger one. 
C) Communities are defined as groups of four or more species within a given area. 
D) Communities are groups of species that do not fluctuate over time.

Question 8

________ consumers feed on primary consumers as part or all of their diet.

Accepted Answer

The answer of ________ consumers feed on primary consumers as...

Question 9

Communities change with respect to several timescales. An example of long-term change would be the

Accepted Answer

A) annual variability in population size. 
B) presence or absence of a migrant species. 
C) species composition of the community. 
D) decline in prey abundance during a harsh winter. 
A) annual variability in population size. 
B) presence or absence of a migrant species. 
C) species composition of the community. 
D) decline in prey abundance during a harsh winter.

Question 10

Match each term to a statement listed below.
-a fish that consumes parasites found on a shark

Accepted Answer

A) mutualism 
B) commensalism 
C) exploitation 
D) competition 
A) mutualism 
B) commensalism 
C) exploitation 
D) competition

Question 11

Undisturbed communities with species compositions that remain stable over time are referred to as

Accepted Answer

A) climax communities. 
B) primary successors. 
C) secondary successors. 
D) keystone communities. 
A) climax communities. 
B) primary successors. 
C) secondary successors. 
D) keystone communities.

Question 12

Match each term to a statement listed below.
-a bird building a nest within a tree

Accepted Answer

A) mutualism 
B) commensalism 
C) exploitation 
D) competition 
A) mutualism 
B) commensalism 
C) exploitation 
D) competition

Question 13

In ________ competition, species compete indirectly for a shared resource, each reducing the amount available to the other competitor.

Accepted Answer

A) exploitative 
B) restrictive 
C) interference 
D) advantageous 
A) exploitative 
B) restrictive 
C) interference 
D) advantageous

Question 14

How does primary succession differ from secondary succession?

Accepted Answer

Primary succession takes place in newly

Question 15

A(n) ________ is a single sequence of who eats whom in a community.

Accepted Answer

The answer of A(n) ________ is a single sequence of...

Question 16

The relationship between house pets and people would be best described as

Accepted Answer

A) parasitic. 
B) mutualistic. 
C) predatorial. 
D) competitive. 
A) parasitic. 
B) mutualistic. 
C) predatorial. 
D) competitive.

Question 17

Which of the following experiments would help to identify a keystone species?

Accepted Answer

A) Introduce more of the suspected species into the area and observe the effects on other community members. 
B) Introduce an invasive species related to the suspected species into the area and observe the effects on the suspected species. 
C) Remove the suspected species from the area and observe the effects on other community members. 
D) Introduce additional individuals of the suspected species' food source into the area and observe the effects on community members. 
A) Introduce more of the suspected species into the area and observe the effects on other community members. 
B) Introduce an invasive species related to the suspected species into the area and observe the effects on the suspected species. 
C) Remove the suspected species from the area and observe the effects on other community members. 
D) Introduce additional individuals of the suspected species' food source into the area and observe the effects on community members.

Question 18

Human cells contain mitochondria, which are responsible for processing the energy needed by our cells. Remember that the ancestors of mitochondria may once have been free-living prokaryotes. If mitochondria were still considered to be separate organisms within our cells, which of the following would best describe our relationship with them?

Accepted Answer

A) parasitic 
B) competitive 
C) mutualistic 
D) pathogenic 
A) parasitic 
B) competitive 
C) mutualistic 
D) pathogenic

Question 19

During ________ a newly created habitat is inhabited.

Accepted Answer

A) primary succession 
B) climax community formation 
C) disturbance colonization 
D) keystone recovery 
A) primary succession 
B) climax community formation 
C) disturbance colonization 
D) keystone recovery

Question 20

Every healthy human digestive system is home to countless microorganisms. In a normal digestive system, what type of relationship would you say this is?

Accepted Answer

A) parasitic 
B) pathological 
C) competitive 
D) mutualistic 
A) parasitic 
B) pathological 
C) competitive 
D) mutualistic

Exam 17: Communities of Organisms

Define the two key pieces of information used to examine diversity within a community.

Which of the following communities would be considered to have the greatest species richness?

How do ecological communities change over time?

Which of the following would probably NOT occur if a single species was removed from an ecological community?

After studying the food web shown, select a reasonable outcome following the complete disappearance of wolves.

Can a human being be considered an ecological community?

Which of the following statements accurately describes an ecological community?

________ consumers feed on primary consumers as part or all of their diet.

Communities change with respect to several timescales. An example of long-term change would be the

Match each term to a statement listed below. -a fish that consumes parasites found on a shark

Undisturbed communities with species compositions that remain stable over time are referred to as

Match each term to a statement listed below. -a bird building a nest within a tree

In ________ competition, species compete indirectly for a shared resource, each reducing the amount available to the other competitor.

How does primary succession differ from secondary succession?

A(n) ________ is a single sequence of who eats whom in a community.

The relationship between house pets and people would be best described as

Which of the following experiments would help to identify a keystone species?

During ________ a newly created habitat is inhabited.

Every healthy human digestive system is home to countless microorganisms. In a normal digestive system, what type of relationship would you say this is?

The Nature of Science

Chemistry of Life

Life Is Cellular

How Cells Work

Cell Division

Patterns of Inheritance

Chromosomes and Human Genetics

What Genes Are

How Genes Work

Evidence for Evolution

Mechanisms of Evolution

Adaptation and Species

The History of Life

Human Evolution

General Principles of Ecology

Growth of Populations

Ecosystems

Homeostasis, Reproduction, and Development

Digestive, Muscular, and Skeletal Systems

Circulatory, Respiratory, Urinary, and Nervous Systems

Endocrine and Immune Systems

Plant Physiology

Applying the Science

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