Question 1

The number of trophic levels in an ecosystem is limited by

Accepted Answer

A) the number of tertiary consumers. 
B) the loss of energy with each transfer between trophic levels. 
C) the gain of energy with each transfer between trophic levels. 
D) the rate at which organisms can recycle energy within the ecosystem. 
E) the rate at which secondary consumers consume their prey. 
A) the number of tertiary consumers. 
B) the loss of energy with each transfer between trophic levels. 
C) the gain of energy with each transfer between trophic levels. 
D) the rate at which organisms can recycle energy within the ecosystem. 
E) the rate at which secondary consumers consume their prey. B

Question 2

The total amount of energy fixed by autotrophs in an ecosystem is called ________________.

Accepted Answer

gross primary production

Question 3

Nitrogen stable isotopes are useful tools for the study of food web structure because isotope ratios

Accepted Answer

A) change in predictable ways across trophic levels. 
B) often vary among alternative food sources for a consumer. 
C) for a predator exactly match the isotope ratio in its prey. 
D) both change in predictable ways across trophic levels and often vary among alternative food sources for a consumer. 
A) change in predictable ways across trophic levels. 
B) often vary among alternative food sources for a consumer. 
C) for a predator exactly match the isotope ratio in its prey. 
D) both change in predictable ways across trophic levels and often vary among alternative food sources for a consumer. D

Question 4

In Hubbard Brook Experimental Forest,the largest "standing stock" of energy is represented by biomass of

Accepted Answer

A) living plant tissues. 
B) dead plant tissues. 
C) invertebrate herbivores. 
D) vertebrate herbivores. 
E) vertebrate carnivores. 
A) living plant tissues. 
B) dead plant tissues. 
C) invertebrate herbivores. 
D) vertebrate herbivores. 
E) vertebrate carnivores.

Question 5

The terrestrial ecosystems with highest primary production are usually those that are

Accepted Answer

A) warm and wet. 
B) warm and dry. 
C) cool and wet. 
D) cool and dry. 
E) intermediate in both temperature and moisture. 
A) warm and wet. 
B) warm and dry. 
C) cool and wet. 
D) cool and dry. 
E) intermediate in both temperature and moisture.

Question 6

Leibig's "Law of the Minimum" stated that

Accepted Answer

A) the lowest primary productivity occurs in the coldest ecosystems. 
B) primary productivity is typically controlled entirely by climate. 
C) primary productivity is typically controlled by both climate and soil nutrients. 
D) a single soil nutrient typically limits primary productivity. 
E) the highest primary productivity occurs at the lowest trophic level. 
A) the lowest primary productivity occurs in the coldest ecosystems. 
B) primary productivity is typically controlled entirely by climate. 
C) primary productivity is typically controlled by both climate and soil nutrients. 
D) a single soil nutrient typically limits primary productivity. 
E) the highest primary productivity occurs at the lowest trophic level.

Question 7

Bowman and his colleagues,who added nutrients to the alpine tundra on Niwot Ridge,Colorado,found

Accepted Answer

A) phosphorus is the main nutrient limiting primary production in all meadows. 
B) nitrogen is the main nutrient limiting primary production in all meadows. 
C) phosphorus is the main nutrient limiting primary production in dry meadows. 
D) nitrogen is the main nutrient limiting primary production in wet meadows. 
E) nitrogen and phosphorus jointly limit primary production in wet meadows. 
A) phosphorus is the main nutrient limiting primary production in all meadows. 
B) nitrogen is the main nutrient limiting primary production in all meadows. 
C) phosphorus is the main nutrient limiting primary production in dry meadows. 
D) nitrogen is the main nutrient limiting primary production in wet meadows. 
E) nitrogen and phosphorus jointly limit primary production in wet meadows.

Question 8

The influences of nutrients and temperatures on ecosystem properties are part of what ecologists call "bottom-up controls."

Accepted Answer

A) True 
 B)False

Question 9

Primary producers make up the first,or basal,____________ in most food webs.

Accepted Answer

The answer of Primary producers make up the first,or basal,____________...

Question 10

You are comparing two population means with a Student's t-Test.If the calculated value of t is greater than the critical value of t,you accept the hypothesis which states that there is a significant difference between the population means.

Accepted Answer

A) True 
 B)False

Question 11

Among marine systems,primary productivity is highest in tropical portions of the major oceans,far from terrestrial influences.

Accepted Answer

A) True 
 B)False

Question 12

The rate of primary production on the Serengeti grassland is positively correlated with

Accepted Answer

A) rainfall. 
B) moderate grazing. 
C) high-intensity grazing. 
D) both rainfall and moderate grazing. 
E) both rainfall and high-intensity grazing. 
A) rainfall. 
B) moderate grazing. 
C) high-intensity grazing. 
D) both rainfall and moderate grazing. 
E) both rainfall and high-intensity grazing.

Question 13

"Actual evapotranspiration" for an ecosystem refers to the amount of water that

Accepted Answer

A) is taken up from soils by plant roots. 
B) evaporates from soils. 
C) is transpired by plants. 
D) evaporates from soils plus the amount transpired by plants. 
E) could evaporate from soils,if they were kept wet at all times. 
A) is taken up from soils by plant roots. 
B) evaporates from soils. 
C) is transpired by plants. 
D) evaporates from soils plus the amount transpired by plants. 
E) could evaporate from soils,if they were kept wet at all times.

Question 14

On the Serengeti plain of eastern Africa,intensive grazing by large mammals greatly decreases primary productivity in the grazed areas.

Accepted Answer

A) True 
 B)False

Question 15

The low productivity of arctic tundra ecosystems results

Accepted Answer

A) entirely because tundra has low evapotranspiration. 
B) entirely because tundra soils are low in nutrients. 
C) entirely because tundra soils retain water poorly. 
D) because tundra soils have low nutrients and retain water poorly. 
E) because tundra has low evapotranspiration and low-nutrient soils. 
A) entirely because tundra has low evapotranspiration. 
B) entirely because tundra soils are low in nutrients. 
C) entirely because tundra soils retain water poorly. 
D) because tundra soils have low nutrients and retain water poorly. 
E) because tundra has low evapotranspiration and low-nutrient soils.

Question 16

In Hubbard Brook Experimental Forest,the fraction of available solar energy fixed by primary producers is

Accepted Answer

A) approximately 2%. 
B) approximately 15%. 
C) approximately 50%. 
D) nearly all of it. 
E) Primary producers do not fix solar energy. 
A) approximately 2%. 
B) approximately 15%. 
C) approximately 50%. 
D) nearly all of it. 
E) Primary producers do not fix solar energy.

Question 17

Net primary productivity is the primary productivity of an ecosystem,after subtracting energy lost in

Accepted Answer

A) dead plant tissues. 
B) inedible plant tissues. 
C) respiration by primary producers. 
D) respiration by primary consumers. 
E) inefficiencies of photosynthesis. 
A) dead plant tissues. 
B) inedible plant tissues. 
C) respiration by primary producers. 
D) respiration by primary consumers. 
E) inefficiencies of photosynthesis.

Question 18

Among lakes,primary productivity seems to be mainly controlled by levels of

Accepted Answer

A) light. 
B) pollutants. 
C) temperature. 
D) nutrients. 
E) None of the choices are correct. 
A) light. 
B) pollutants. 
C) temperature. 
D) nutrients. 
E) None of the choices are correct.

Question 19

An organism's _________ describes its feeding position within an ecosystem.

Accepted Answer

A) prey level 
B) production level 
C) consumption level 
D) trophic level 
E) predator level 
A) prey level 
B) production level 
C) consumption level 
D) trophic level 
E) predator level

Question 20

The "trophic cascade hypothesis" emphasizes the role of

Accepted Answer

A) nutrients in controlling primary productivity. 
B) nutrients in controlling primary consumption. 
C) consumers in controlling primary productivity. 
D) grazing by herbivores in controlling ecosystem nutrient levels. 
E) primary productivity in controlling primary and secondary consumption. 
A) nutrients in controlling primary productivity. 
B) nutrients in controlling primary consumption. 
C) consumers in controlling primary productivity. 
D) grazing by herbivores in controlling ecosystem nutrient levels. 
E) primary productivity in controlling primary and secondary consumption.

Exam 18: Primary Production and Energy Flow

The number of trophic levels in an ecosystem is limited by

The total amount of energy fixed by autotrophs in an ecosystem is called ________________.

Nitrogen stable isotopes are useful tools for the study of food web structure because isotope ratios

In Hubbard Brook Experimental Forest,the largest "standing stock" of energy is represented by biomass of

The terrestrial ecosystems with highest primary production are usually those that are

Leibig's "Law of the Minimum" stated that

Bowman and his colleagues,who added nutrients to the alpine tundra on Niwot Ridge,Colorado,found

The influences of nutrients and temperatures on ecosystem properties are part of what ecologists call "bottom-up controls."

Primary producers make up the first,or basal,____________ in most food webs.

You are comparing two population means with a Student's t-Test.If the calculated value of t is greater than the critical value of t,you accept the hypothesis which states that there is a significant difference between the population means.

Among marine systems,primary productivity is highest in tropical portions of the major oceans,far from terrestrial influences.

The rate of primary production on the Serengeti grassland is positively correlated with

"Actual evapotranspiration" for an ecosystem refers to the amount of water that

On the Serengeti plain of eastern Africa,intensive grazing by large mammals greatly decreases primary productivity in the grazed areas.

The low productivity of arctic tundra ecosystems results

In Hubbard Brook Experimental Forest,the fraction of available solar energy fixed by primary producers is

Net primary productivity is the primary productivity of an ecosystem,after subtracting energy lost in

Among lakes,primary productivity seems to be mainly controlled by levels of

An organism's _________ describes its feeding position within an ecosystem.

The "trophic cascade hypothesis" emphasizes the role of

Introduction to Ecology: Historical Foundations and Developing Frontiers

Life on Land

Life in Water

Population Genetics and Natural Selection

Temperature Relations

Water Relations

Energy and Nutrient Relations

Social Relations

Population Distribution and Abundance

Population Dynamics

Population Growth

Life Histories

Competition

Exploitative Interactions: Predation, herbivory, parasitism, and Disease

Mutualism

Species Abundance and Diversity

Species Interactions and Community Structure

Nutrient Cycling and Retention

Succession and Stability

Landscape Ecology

Geographic Ecology

Global Ecology

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