Question 1

The Hubbard Brook watershed deforestation experiment yielded all of the following results except which of the following?

Accepted Answer

A)  Most minerals were recycled within a forest ecosystem. 
B)  Calcium levels remained high in the soil of deforested areas. 
C)  Deforestation increased water runoff. 
D)  The nitrate concentration in waters draining the deforested area became dangerously high. 
A)  Most minerals were recycled within a forest ecosystem. 
B)  Calcium levels remained high in the soil of deforested areas. 
C)  Deforestation increased water runoff. 
D)  The nitrate concentration in waters draining the deforested area became dangerously high. B

Question 2

Why do logged tropical rain forest soils typically have nutrient-poor soils?

Accepted Answer

A)  Tropical bedrock contains little phosphorous. 
B)  Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria. 
C)  Most of the nutrients in the ecosystem are removed in the harvested timber. 
D)  The cation exchange capacity of the soil is reversed as a result of logging. 
A)  Tropical bedrock contains little phosphorous. 
B)  Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria. 
C)  Most of the nutrients in the ecosystem are removed in the harvested timber. 
D)  The cation exchange capacity of the soil is reversed as a result of logging. C

Question 3

Which trophic level is most vulnerable to extinction?

Accepted Answer

A)  producer level 
B)  primary consumer level 
C)  secondary consumer level 
D)  tertiary consumer level 
A)  producer level 
B)  primary consumer level 
C)  secondary consumer level 
D)  tertiary consumer level D

Question 4

Which of these ecosystems has the lowest net primary production per square meter?

Accepted Answer

A)  a salt marsh 
B)  an open ocean 
C)  a coral reef 
D)  a tropical rain forest 
A)  a salt marsh 
B)  an open ocean 
C)  a coral reef 
D)  a tropical rain forest

Question 5

Which of the following has the greatest effect on the rate of chemical cycling within an
Ecosystem?

Accepted Answer

A)  the ecosystem's rate of primary production 
B)  the secondary production efficiency of the ecosystem's consumers 
C)  the rate of decomposition in the ecosystem 
D)  the trophic efficiency of the ecosystem 
A)  the ecosystem's rate of primary production 
B)  the secondary production efficiency of the ecosystem's consumers 
C)  the rate of decomposition in the ecosystem 
D)  the trophic efficiency of the ecosystem

Question 6

Use the following figure to answer the question.
 
In the figure, what could the jagged arrow leaving microorganisms and other detritivores represent?

Accepted Answer

A)  organic compounds broken down by bacteria 
B)  energy consumed by bacteria 
C)  energy lost from a worm during cellular respiration 
D)  CO₂ and heat loss from decomposing materials due to the effects of solar radiation and precipitation 
A)  organic compounds broken down by bacteria 
B)  energy consumed by bacteria 
C)  energy lost from a worm during cellular respiration 
D)  CO₂ and heat loss from decomposing materials due to the effects of solar radiation and precipitation

Question 7

Use the following figure to answer the question.
 
Diagram of a food web (arrows represent energy flow and letters represent species)
If the figure represents a terrestrial food web, the combined biomass of C + D would probably be ________.

Accepted Answer

A)  greater than the biomass of A 
B)  greater than the biomass of B 
C)  less than the biomass of A + B 
D)  less than the biomass of E 
A)  greater than the biomass of A 
B)  greater than the biomass of B 
C)  less than the biomass of A + B 
D)  less than the biomass of E

Question 8

During a year, plants never use 100% of the incoming solar radiation for photosynthesis. What is a reasonable explanation for this?

Accepted Answer

A)  Plants cannot photosynthesize as well in warm temperatures as in cold temperatures. 
B)  Plants do not intercept all incoming light, as some light will strike water, bare soil, or rock. 
C)  The pigments that drive photosynthesis absorb all of the wavelengths of light that are available; however, some of the light is subsequently reflected. 
D)  At least 75% of all incoming light is reflected, absorbed, or scattered back by clouds in the atmosphere. 
A)  Plants cannot photosynthesize as well in warm temperatures as in cold temperatures. 
B)  Plants do not intercept all incoming light, as some light will strike water, bare soil, or rock. 
C)  The pigments that drive photosynthesis absorb all of the wavelengths of light that are available; however, some of the light is subsequently reflected. 
D)  At least 75% of all incoming light is reflected, absorbed, or scattered back by clouds in the atmosphere.

Question 9

Acid precipitation lowered the pH of soil in a terrestrial ecosystem that supported a diverse community of plants and animals. The decrease in pH eliminated all nitrogen-fixing bacteria populations in the area. Which prediction most accurately reflects the impact this will have on the community?

Accepted Answer

A)  Since phosphorus can replace nitrogen as an essential nutrient, the impact will be minimal. 
B)  Plants can obtain the nitrogen necessary for growth from the atmosphere, but bacterial communities will be negatively impacted. 
C)  Primary producers will suffer from nitrogen deficiency and the entire community will experience a decrease in carrying capacity. 
D)  The decrease in pH actually increases the availability of soil nutrients, so other nutrients that were less available cause an increase in primary production and an increase in biomass at other trophic levels. 
A)  Since phosphorus can replace nitrogen as an essential nutrient, the impact will be minimal. 
B)  Plants can obtain the nitrogen necessary for growth from the atmosphere, but bacterial communities will be negatively impacted. 
C)  Primary producers will suffer from nitrogen deficiency and the entire community will experience a decrease in carrying capacity. 
D)  The decrease in pH actually increases the availability of soil nutrients, so other nutrients that were less available cause an increase in primary production and an increase in biomass at other trophic levels.

Question 10

How can biodiversity affect the way we decontaminate industrial sites?
I.Bacteria have been found to be able to detoxify certain chemicals; perhaps there are more.
II.Trees produce sawdust, which can be used to soak up chemicals.
III.Species evolving in contaminated areas could adapt and detoxify the area.

Accepted Answer

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

Question 11

If you applied a fungicide to a cornfield, what would you expect to happen to the rate of decomposition and net ecosystem production (NEP)?

Accepted Answer

A)  Both decomposition rate and NEP would decrease. 
B)  Neither would change. 
C)  Decomposition rate would increase and NEP would decrease. 
D)  Decomposition rate would decrease and NEP would increase. 
A)  Both decomposition rate and NEP would decrease. 
B)  Neither would change. 
C)  Decomposition rate would increase and NEP would decrease. 
D)  Decomposition rate would decrease and NEP would increase.

Question 12

Which of the following would be considered an example of bioremediation?

Accepted Answer

A)  adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability 
B)  using a bulldozer to regrade a strip mine 
C)  dredging a river bottom to remove contaminated sediments 
D)  adding fertilizer to soil poor in nutrients to increase plant growth 
A)  adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability 
B)  using a bulldozer to regrade a strip mine 
C)  dredging a river bottom to remove contaminated sediments 
D)  adding fertilizer to soil poor in nutrients to increase plant growth

Question 13

You own 300 acres of patchy temperate forest mixed with grassy meadows. Which one of the following actions would increase the net primary productivity of the area the most?

Accepted Answer

A)  adding fertilizer to the entire area 
B)  introducing 100 rabbits into the area 
C)  planting 500 new trees 
D)  relocating all of the deer found in the area 
A)  adding fertilizer to the entire area 
B)  introducing 100 rabbits into the area 
C)  planting 500 new trees 
D)  relocating all of the deer found in the area

Question 14

How does inefficient transfer of energy among trophic levels result in the typically high endangerment status of many top-level predators?

Accepted Answer

A)  Top-level predators are destined to have small populations that are sparsely distributed. 
B)  Predators have relatively large population sizes. 
C)  Predators are more disease-prone than animals at lower trophic levels. 
D)  Top-level predators are more likely to be stricken with parasites. 
A)  Top-level predators are destined to have small populations that are sparsely distributed. 
B)  Predators have relatively large population sizes. 
C)  Predators are more disease-prone than animals at lower trophic levels. 
D)  Top-level predators are more likely to be stricken with parasites.

Question 15

The goal of restoration ecology is to ________.

Accepted Answer

A)  replace a ruined ecosystem with a more suitable ecosystem for that area 
B)  return degraded ecosystems to a more natural state 
C)  manage competition among species in human-altered ecosystems 
D)  prevent further degradation by protecting an area with park status 
A)  replace a ruined ecosystem with a more suitable ecosystem for that area 
B)  return degraded ecosystems to a more natural state 
C)  manage competition among species in human-altered ecosystems 
D)  prevent further degradation by protecting an area with park status

Question 16

If the sun were to suddenly stop providing energy to Earth, most ecosystems would eventually vanish. Which of the following ecosystems would likely survive the longest after this hypothetical disaster?

Accepted Answer

A)  pelagic ocean 
B)  tundra 
C)  deep benthic ocean 
D)  a desert spring 
A)  pelagic ocean 
B)  tundra 
C)  deep benthic ocean 
D)  a desert spring

Question 17

Use the following figure to answer the question.
 
Considering its total area covered, which ecosystem type represented in the figure has a very low level of economic impact on Earth's ecosystem?

Accepted Answer

A)  tropical wet forest 
B)  rock, sand, and ice 
C)  tropical seasonal forest 
D)  ocean neritic zone 
A)  tropical wet forest 
B)  rock, sand, and ice 
C)  tropical seasonal forest 
D)  ocean neritic zone

Question 18

To recycle nutrients, an ecosystem must have, at a minimum, ________.

Accepted Answer

A)  producers 
B)  producers and decomposers 
C)  producers, primary consumers, and decomposers 
D)  producers, primary consumers, secondary consumers, and decomposers 
A)  producers 
B)  producers and decomposers 
C)  producers, primary consumers, and decomposers 
D)  producers, primary consumers, secondary consumers, and decomposers

Question 19

Which of the following organisms is correctly paired with its trophic level?

Accepted Answer

A)  cyanobacterium-primary consumer 
B)  grasshopper-secondary consumer 
C)  phytoplankton-primary producer 
D)  fungus-primary consumer 
A)  cyanobacterium-primary consumer 
B)  grasshopper-secondary consumer 
C)  phytoplankton-primary producer 
D)  fungus-primary consumer

Question 20

Use the following figure to answer the question.
 
On the diagram of the nitrogen cycle, which number represents the ammonium ion (NH₄⁺)?

Accepted Answer

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

Exam 55: Ecosystems and Restoration Ecology

The Hubbard Brook watershed deforestation experiment yielded all of the following results except which of the following?

Why do logged tropical rain forest soils typically have nutrient-poor soils?

Which trophic level is most vulnerable to extinction?

Which of these ecosystems has the lowest net primary production per square meter?

Which of the following has the greatest effect on the rate of chemical cycling within an Ecosystem?

Use the following figure to answer the question. In the figure, what could the jagged arrow leaving microorganisms and other detritivores represent?

Use the following figure to answer the question. Diagram of a food web (arrows represent energy flow and letters represent species) If the figure represents a terrestrial food web, the combined biomass of C + D would probably be ________.

During a year, plants never use 100% of the incoming solar radiation for photosynthesis. What is a reasonable explanation for this?

Acid precipitation lowered the pH of soil in a terrestrial ecosystem that supported a diverse community of plants and animals. The decrease in pH eliminated all nitrogen-fixing bacteria populations in the area. Which prediction most accurately reflects the impact this will have on the community?

If you applied a fungicide to a cornfield, what would you expect to happen to the rate of decomposition and net ecosystem production (NEP)?

Which of the following would be considered an example of bioremediation?

You own 300 acres of patchy temperate forest mixed with grassy meadows. Which one of the following actions would increase the net primary productivity of the area the most?

How does inefficient transfer of energy among trophic levels result in the typically high endangerment status of many top-level predators?

The goal of restoration ecology is to ________.

If the sun were to suddenly stop providing energy to Earth, most ecosystems would eventually vanish. Which of the following ecosystems would likely survive the longest after this hypothetical disaster?

Use the following figure to answer the question. Considering its total area covered, which ecosystem type represented in the figure has a very low level of economic impact on Earth's ecosystem?

To recycle nutrients, an ecosystem must have, at a minimum, ________.

Which of the following organisms is correctly paired with its trophic level?

Use the following figure to answer the question. On the diagram of the nitrogen cycle, which number represents the ammonium ion (NH₄⁺)?

Evolution, the Themes of Biology, and Scientific Inquiry

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

Gene Expression: 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

Vascular 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 Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Conservation Biology and Global Change

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