Question 1

Which response variable (on the y axis)  did NOT increase with plant species richness?

Accepted Answer

A)   stability of herbivore species richness
B)   stability of herbivore abundance
C)   stability of predator and parasite species richness
D)   stability of predator and parasite abundance

Question 2

You are sampling a stream with a net, collecting 100 macroinvertebrates. Your collection is as follows (assume the different macroinvertebrate types noted are all the same species (e.g., 17 mayflies are all of the same species) : 5 caddisflies, 17 mayflies, 48 stoneflies, 6 dragonflies, 10 damselflies, 4 alderflies, 2 dobsonflies, 2 midges, 3 crayfish, 1 aquatic sowbug, 1 water penny, 1 cranefly
If you were to take this data and construct a rank abundance curve, what would it look like?

Accepted Answer

A)   a straight line sloped upward
B)   a straight line sloped downward
C)   a curve that starts off relatively level on the left side and curving steeply upward on the right
D)   a curve initially very steeply downward on the left side and leveling off on the right

Question 3

What, in addition to tolerance to soil characteristics, might account for the distribution of plant species over different soil types?

Accepted Answer

In addition to tolerance to soil charact...

Question 4

What community measure does Shannon's index quantify?

Accepted Answer

A)   the number of species
B)   relative abundance of species
C)   species richness
D)   species diversity

Question 5

Which statement best reflects the relationship between a disturbance and an alternative stable state?

Accepted Answer

A)   Many communities alternate between stable states on a seasonal basis, which is not a true disturbance.
B)   A community may achieve an alternative stable state only after a major disturbance.
C)   An alternative stable state will not happen in aquatic communities, where there is no fire and water is not limiting.
D)   Communities can alternate among stable states in the absence of disturbance.

Question 6

The dams that have been built on many rivers stabilize river flow by increasing flows below the dam during droughts and decreasing the amount of flooding during periods of high rainfall. Explain how these stabilized flows can be considered as a disturbance.

Accepted Answer

The stabilized flows created by dams can...

Question 7

What species richness-productivity relationship has the Park Grass Experiment in England demonstrated over the past 150 years?

Accepted Answer

A)   U-shaped
B)   negative
C)   none
D)   positive
E)   hump-shaped

Question 8

A researcher removed predatory starfish from sections of intertidal rock and found that the number of prey species decreased by 50 percent relative to control plots within a short time. This indicates that

Accepted Answer

A)   predators compete with prey for space.
B)   predator species are competing for prey.
C)   starfish predation increases prey diversity.
D)   starfish predation reduces prey diversity. C

Question 9

What would be the most likely species richness-productivity relationship for a community in which the species were not resource limited?

Accepted Answer

A)   U-shaped
B)   negative
C)   none
D)   positive
E)   hump-shaped

Question 10

Carbon dioxide with radioactive carbon was bubbled into an illuminated aquarium containing unfiltered pond water. In what order will radioactivity appear in various organisms in the aquarium?

Accepted Answer

A)   herbivores, carnivores, producers
B)   producers, herbivores, carnivores
C)   producers, carnivores, herbivores
D)   herbivores, producers, carnivores
E)   All organisms will take up radioactive carbon simultaneously.

Question 11

The presence of fish has a positive effect on shoreline flowering plants. Which lines in the diagram reflect a negative direct effect?

Accepted Answer

A)   fish  →\rightarrow→  adult dragonfly
B)   fish  →\rightarrow→  pollinator
C)   fish  →\rightarrow→  larval dragonfly
D)   adult dragonfly  →\rightarrow→  plants

Question 12

Explain the relationships that appear to reduce tadpole abundance when insecticide is present, even though insecticide does not directly affect tadpoles.

Accepted Answer

There are several possible relationships...

Question 13

Why are keystone species important in food webs?

Accepted Answer

Keystone species play a critical role in...

Question 14

What most accurately describes a trophic cascade?

Accepted Answer

A)   bottom-up effects
B)   top-down effects
C)   found in waterfall habitats
D)   is based on two trophic levels

Question 15

Using the figure that follows, compare species richness and evenness.

Accepted Answer

The answer of Using the figure that follows, compare species...

Question 16

Explain what the intermediate disturbance hypothesis predicts for the comparison of species richness in forests where fires have been suppressed versus those with unsuppressed natural fire.

Accepted Answer

The intermediate disturbance hypothesis ...

Question 17

The plot shows that most species in this community are

Accepted Answer

A)   moderately abundant.
B)   very rare.
C)   very abundant.
D)   about evenly distributed. A

Question 18

Consider invertebrates such as starfish and mussels on a rocky intertidal habitat where tidal cycles cause the animals to move between exposure and submersion. Are these changing conditions considered a disturbance?

Accepted Answer

In ecological terms, a disturbance is an...

Question 19

What is the suggested mechanism by which the presence of insecticide influences phytoplankton abundance?

Accepted Answer

A)   Periphyton abundance is reduced by insecticide.
B)   Tadpoles consume phytoplankton when periphyton is reduced in abundance.
C)   The reduction of zooplankton by insecticide reduces herbivory on phytoplankton, which increases abundance.
D)   Inert chemicals in the insecticide include nitrogen, which promotes phytoplankton growth. C

Question 20

How would adding resources such as fertilizer to an area affect the species in a community?

Accepted Answer

A)   It would reduce richness.
B)   It would increase richness.
C)   It would increase the abundance of all species.
D)   It would reduce the abundance of all species.

Exam 18: Community Structure

Which response variable (on the y axis) did NOT increase with plant species richness?

Correct Answer
verified

Correct Answer
verified

What, in addition to tolerance to soil characteristics, might account for the distribution of plant species over different soil types?

Correct Answer
Answered by ExamLex AI
In addition to tolerance to soil charact...
View Answer

What community measure does Shannon's index quantify?

Correct Answer
verified

Which statement best reflects the relationship between a disturbance and an alternative stable state?

Correct Answer
verified

The dams that have been built on many rivers stabilize river flow by increasing flows below the dam during droughts and decreasing the amount of flooding during periods of high rainfall. Explain how these stabilized flows can be considered as a disturbance.

Correct Answer
Answered by ExamLex AI
The stabilized flows created by dams can...
View Answer

What species richness-productivity relationship has the Park Grass Experiment in England demonstrated over the past 150 years?

Correct Answer
verified

A researcher removed predatory starfish from sections of intertidal rock and found that the number of prey species decreased by 50 percent relative to control plots within a short time. This indicates that

Correct Answer
verified
C

What would be the most likely species richness-productivity relationship for a community in which the species were not resource limited?

Correct Answer
verified

Carbon dioxide with radioactive carbon was bubbled into an illuminated aquarium containing unfiltered pond water. In what order will radioactivity appear in various organisms in the aquarium?

Correct Answer
verified

Correct Answer
verified

Explain the relationships that appear to reduce tadpole abundance when insecticide is present, even though insecticide does not directly affect tadpoles.

Correct Answer
Answered by ExamLex AI
There are several possible relationships...
View Answer

Why are keystone species important in food webs?

Correct Answer
Answered by ExamLex AI
Keystone species play a critical role in...
View Answer

What most accurately describes a trophic cascade?

Correct Answer
verified

Using the figure that follows, compare species richness and evenness.

Correct Answer
verified

Explain what the intermediate disturbance hypothesis predicts for the comparison of species richness in forests where fires have been suppressed versus those with unsuppressed natural fire.

Correct Answer
Answered by ExamLex AI
The intermediate disturbance hypothesis ...
View Answer

The plot shows that most species in this community are

Correct Answer
verified
A

Consider invertebrates such as starfish and mussels on a rocky intertidal habitat where tidal cycles cause the animals to move between exposure and submersion. Are these changing conditions considered a disturbance?

Correct Answer
Answered by ExamLex AI
In ecological terms, a disturbance is an...
View Answer

What is the suggested mechanism by which the presence of insecticide influences phytoplankton abundance?

Correct Answer
verified
C

How would adding resources such as fertilizer to an area affect the species in a community?

Correct Answer
verified

Exam 18: Community Structure

Which response variable (on the y axis) did NOT increase with plant species richness?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What, in addition to tolerance to soil characteristics, might account for the distribution of plant species over different soil types?

Correct AnswerAnswered by ExamLex AIIn addition to tolerance to soil charact...View AnswerShow Answer

What community measure does Shannon's index quantify?

Correct AnswerverifiedShow Answer

Which statement best reflects the relationship between a disturbance and an alternative stable state?

Correct AnswerverifiedShow Answer

The dams that have been built on many rivers stabilize river flow by increasing flows below the dam during droughts and decreasing the amount of flooding during periods of high rainfall. Explain how these stabilized flows can be considered as a disturbance.

Correct AnswerAnswered by ExamLex AIThe stabilized flows created by dams can...View AnswerShow Answer

What species richness-productivity relationship has the Park Grass Experiment in England demonstrated over the past 150 years?

Correct AnswerverifiedShow Answer

A researcher removed predatory starfish from sections of intertidal rock and found that the number of prey species decreased by 50 percent relative to control plots within a short time. This indicates that

Correct AnswerverifiedC

What would be the most likely species richness-productivity relationship for a community in which the species were not resource limited?

Correct AnswerverifiedShow Answer

Carbon dioxide with radioactive carbon was bubbled into an illuminated aquarium containing unfiltered pond water. In what order will radioactivity appear in various organisms in the aquarium?

Correct AnswerverifiedShow Answer

The presence of fish has a positive effect on shoreline flowering plants. Which lines in the diagram reflect a negative direct effect?

Correct AnswerverifiedShow Answer

Explain the relationships that appear to reduce tadpole abundance when insecticide is present, even though insecticide does not directly affect tadpoles.

Correct AnswerAnswered by ExamLex AIThere are several possible relationships...View AnswerShow Answer

Why are keystone species important in food webs?

Correct AnswerAnswered by ExamLex AIKeystone species play a critical role in...View AnswerShow Answer

What most accurately describes a trophic cascade?

Correct AnswerverifiedShow Answer

Using the figure that follows, compare species richness and evenness.

Correct AnswerverifiedShow Answer

Explain what the intermediate disturbance hypothesis predicts for the comparison of species richness in forests where fires have been suppressed versus those with unsuppressed natural fire.

Correct AnswerAnswered by ExamLex AIThe intermediate disturbance hypothesis ...View AnswerShow Answer

The plot shows that most species in this community are

Correct AnswerverifiedA

Consider invertebrates such as starfish and mussels on a rocky intertidal habitat where tidal cycles cause the animals to move between exposure and submersion. Are these changing conditions considered a disturbance?

Correct AnswerAnswered by ExamLex AIIn ecological terms, a disturbance is an...View AnswerShow Answer

What is the suggested mechanism by which the presence of insecticide influences phytoplankton abundance?

Correct AnswerverifiedC

How would adding resources such as fertilizer to an area affect the species in a community?

Correct AnswerverifiedShow Answer

Exam 18: Community Structure　

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
In addition to tolerance to soil charact...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The stabilized flows created by dams can...
View Answer

Correct Answer
verified

Correct Answer
verified
C

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
There are several possible relationships...
View Answer

Correct Answer
Answered by ExamLex AI
Keystone species play a critical role in...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
Answered by ExamLex AI
The intermediate disturbance hypothesis ...
View Answer

Correct Answer
verified
A

Correct Answer
Answered by ExamLex AI
In ecological terms, a disturbance is an...
View Answer

Correct Answer
verified
C

Correct Answer
verified