Environment and Ecology Final Exam Review
Completion
Complete each statement.
1. Bacteria and fungi are known as ____________________ because they break down the remains of organisms.
2. The energy role of a grizzly bear is that of a(n) ____________________ because it cannot make its own food.
3. A diagram called a(n) _________________________ shows how much energy is available at each level of a
food web.
4. The least amount of energy is available at the ____________________ level of an energy pyramid.
5. The energy role of the first organism in a food chain is always a(n) ____________________.
6. An organism that eats only plants is a(n) ____________________ consumer.
7. Water vapor turns into droplets of liquid water in the process of ____________________.
8. Water from a lake changes to the gas state in the process of ____________________.
9. Certain bacteria change nitrogen gas into a usable form in a process called _________________________.
10. Producers use carbon from the gas _________________________ to make sugars and starches.
11. The distribution of species has been affected by the slow movement of Earth’s continents called
_________________________.
12. Temperature and precipitation determine an area’s ____________________, which can limit dispersal of
organisms.
13. The ____________________ biome receives less than 25 centimeters of rain a year and may have large
temperature shifts every day.
14. The soil that is frozen all year in the tundra is called ____________________.
15. Places with similar ____________________ tend to have species that occupy similar niches.
16. The process of burning gasoline in a car engine to release energy is called ____________________.
17. In a power plant, fuel is burned to boil water, producing ____________________ which then turns the blades
of a turbine.
18. Fossil fuels are made of energy-rich chemical compounds called ____________________.
19. A liquid fossil fuel formed from the remains of animals, algae, and other organisms is
____________________.
20. Petrochemicals are compounds that are made from the fossil fuel ____________________.
21. Crude oil is heated and separated into fuels and other products in a(n) ____________________.
22. Many calculators contain ____________________ that convert solar energy into electricity.
23. Some solar plants use giant ____________________ that focus the sun’s rays to heat water.
24. The intense heat from Earth’s interior is called ____________________ energy.
25. Wood, leaves, and manure belong to a group of renewable energy sources called ____________________
fuels.
26. The process of nuclear fission begins when a(n) ____________________ strikes the nucleus of an atom.
27. When the neutrons released by a fission reaction continue striking more nuclei, a(n)
_________________________ occurs.
28. In a nuclear power plant, thermal energy released by _________________________ reactions is used to
change water into steam.
29. If the fuel rods in a reactor vessel produce too much heat, a condition called a(n) ____________________
may occur.
30. Taking a bike ride instead of a car ride is practicing energy ____________________, which helps save fuel
for the future.
31. One way to get more energy out of fuels is to increase ____________________, the percentage of energy
used for work.
32. You can conserve energy by using _________________________ instead of air conditioners.
33. You can conserve energy by ____________________ aluminum cans.
34. Wind and hydroelectric power are both indirect forms of ____________________ energy.
35. If fossil fuels continue to be used more rapidly than they are formed, the reserves will eventually be
____________________.
36. Building a highway is an example of the type of land use known as ____________________.
37. The process of replacing topsoil and planting grass to restore a former mining area is called
_________________________.
38. Biodegradable wastes such as grass clippings and food scraps can be disposed of by ____________________
rather than being buried in a landfill.
39. The trash that is produced in your home and school is called ______________________________.
40. The “three R’s” of solid waste management include reduce, ____________________, and recycle.
41. A vehicle with a sign that says “poison” is transporting a(n) ____________________ hazardous waste.
42. A child accidentally drinking a poison is an example of ____________________ exposure to hazardous
materials.
43. Soil forms from the material, called ____________________, that makes up Earth’s crust.
44. A radioactive gas that is naturally formed by certain types of rocks underground is called
____________________.
45. The ozone layer is important because it helps to screen out harmful ____________________ radiation.
46. Gases called _________________________ block the cycle in the ozone layer that absorbs ultraviolet
radiation.
47. Water vapor and carbon dioxide cause the _________________________, the trapping of heat near Earth’s
surface.
48. People cannot use most of the fresh water on Earth because it is in the form of ____________________.
49. People may not have enough water during a(n) ___________________, a period when rainfall is below
normal.
50. One type of water pollution is ____________________ from water that has been used to cool down factory
machinery.
51. The Clean Air Act has resulted in the development of many new types of ____________________ to control
air pollution.
52. Filters and settling tanks remove solid materials from wastewater during the ____________________
treatment step.
53. Certain gases react with water vapor in the air to form acids that return to Earth’s surface as
____________________.
54. The main chemical in photochemical smog is ____________________, which forms when sunlight reacts
with certain gases.
55. Two ways to reduce water pollution are to treat wastes and to find substitutes for ____________________.
56. Burning coal can cause a harmful change to the environment known as _________________________.
57. Trees are examples of ____________________ resources because they can be naturally replaced as they are
used.
58. The study of the natural processes in the environment and how humans can affect them is called
______________________________.
59. A good environmental proposal’s short-term costs should be outweighed by its long-term
____________________.
60. To help balance different viewpoints on an issue, decision makers weigh the ____________________ and
benefits of a proposal.
61. Forests can be described as ____________________ resources because new trees can be planted to replace
trees that are cut down.
62. A(n) _________________________ is a regular amount of a renewable resource that can be harvested
without reducing the future supply.
63. The factor that probably accounts for the great biodiversity in coral reefs is their diversity of
____________________.
64. Wildlife tourism, or “ecotourism,” is an example of the ____________________ value of biodiversity.
65. A species that influences the survival of many other species in an ecosystem is called
a(n) _________________________.
66. The Endangered Species Act is an example of a(n) ____________________ approach to protecting individual
species.
67. Setting aside a marsh as a wildlife refuge is an example of the _________________________ approach to
protecting biodiversity.
68. A diverse pool of ____________________ helps ensure that individuals in a species will pass a variety of
traits to their offspring.
69. One reason to preserve biodiversity is to discover new ____________________ that can be used to treat
illnesses in people.
70. Earth’s most diverse ecosystems are tropical ____________________ and coral reefs.
71. The illegal killing or removal of wildlife species from their habitats is called ____________________.
72. Almost half of all medicines sold today contain ____________________ originally found in wild organisms.
73. The part of an ecosystem where an organism lives and feeds is called the organism’s
____________________.
74. All the biotic and abiotic factors in an area together make up a(n) ____________________.
75. Prairie dogs, snakes, and grass make up a level of ecological organization called a(n)
____________________.
76. Water, sunlight, and soil are ____________________ factors in an ecosystem.
77. Two abiotic factors that are needed for photosynthesis are sunlight and ____________________.
78. Scientists who study how living things interact with the environment are called ____________________.
79. The ____________________ method of estimating involves multiplying the number of organisms in a small
area to find the number in a larger area.
80. The main way that populations increase in size is through the ____________________ of offspring.
81. If food is scarce, it becomes a(n) ____________________ factor that prevents population growth.
82. A lack of places to build nests is an example of ____________________ as a limiting factor for a population
of birds.
83. The thick fur of a polar bear is a(n) ____________________ that allows the bear to live successfully in its
environment.
84. Ticks feed on the blood of mice in a symbiotic relationship called ____________________.
85. A close relationship between two species that benefits at least one of the species is known as
____________________.
86. The struggle of two species to occupy a certain niche in an ecosystem is an example of
____________________.
87. A hawk building a nest on the arm of a cactus without hurting the cactus is an example of the symbiotic
relationship called ____________________.
88. A flea is a parasite that lives on a(n) ____________________ such as a dog.
89. The study of how living things interact with each other and with their environment is called
____________________.
90. The type of succession that occurs in an area where an ecosystem has been disturbed, but where soil and
organisms still exist, is called ____________________ succession.
Short Answer
Use the diagram to answer each question.
91. Which organisms shown are producers?
92. Which organisms shown are consumers?
93. What would happen to the other organisms if all the plants in this ecosystem died?
94. Use the organisms pictured in this ecosystem to construct a food chain.
95. Approximately what percentage of the energy in the plants is passed on to the animals that eat them?
96. Why are there relatively few third-level consumers like bears in an ecosystem?
Use the diagram to answer each question.
97. Which number represents the organisms responsible for converting nitrogen gas into a usable form of
nitrogen?
98. Which number represents the form of nitrogen that can be used by plants?
99. Describe three roles bacteria play in the nitrogen cycle.
100. Explain the role of an animal such as the horse in the nitrogen cycle.
101. Which number represents a group of organisms that break down the wastes and remains of other organisms?
102. On what part of a plant do the organisms represented by number 8 live?
Use the diagram to answer each question.
103. Identify Part A. What is this structure? What is it made of in most reactors?
104. What part of the power plant is used to control the speed of the nuclear reaction? How does it work?
105. Identify Part E. What function does it perform?
106. Explain the purpose of the heat exchanger in the nuclear power plant.
107. Which letter identifies the reactor vessel? What takes place in the reactor vessel?
108. What is the steam in pipe F used for?
Use the diagram to answer each question.
Electricity Production by Energy Source
109. Which of the energy sources shown are fossil fuels?
110. Which energy sources shown are considered to be renewable?
111. Which energy source produces the greatest percentage of electricity?
112. Which two of the named sources shown produce the most air pollution? Which two produce the least?
113. What type of nuclear reaction is currently used to produce electricity?
114. Predict how this graph is likely to change 100 years from now. Explain your answer.
Use the diagram to answer each question.
115. Explain how air emissions from industries can also pollute rainwater.
116. How much greater are the carbon monoxide emissions from non-diesel than from diesel motor vehicles?
(Hint: Set up a ratio of non-diesel sources to diesel sources.)
117. Which of the sources listed are always related to human activities? Which sources could be natural sources of
carbon monoxide?
118. Suggest two ways that the emissions from the largest source listed could be decreased.
119. What percentage of carbon monoxide emissions comes from industry and agriculture?
120. What is the total percentage of carbon monoxide emissions from transportation?
Use the diagram to answer question.
121. Name two gases that would be included in the label “greenhouse gases” in the figure.
122. In the diagram, what is shown by the two arrows that start at Earth’s surface and then bend back toward
Earth?
123. What does the theory of global warming state is happening to the greenhouse effect?
124. What is one source on Earth of carbon dioxide?
125. Predict one possible effect of an increase in Earth’s temperature as a result of a stronger greenhouse effect.
126. What is the original source of the heat that is trapped by the greenhouse effect?
Use the diagram to answer each question.
127. How did the eggshell thicknesses of bird species A and B change between 1945 and 1950?
128. How is eggshell thickness related to the survival of bird species A and B?
129. How might bird species A and B come into contact with DDT, a pesticide used by farmers?
130. Which species of bird has a thicker eggshell?
131. What happened to the eggshell thickness of both species after 1973? Suggest a reason for this change.
132. Had the eggshells of either species returned to their original thickness by 1980? Suggest a reason to explain
your answer.
Use the diagram to answer each question.
133. How has the world population changed since 1650?
134. About how many years did it take the world population to increase from 1 billion to 2 billion people?
135. About how many years did it take the world population to increase from 4 billion to 5 billion people?
136. What are some reasons for the change in the human population after 1650?
137. What effects does a rapidly growing human population have on natural resources?
138. By how many people has the human population grown in the time period shown?
Use the diagram to answer each question.
139. Describe two things the prairie dogs need to live that they obtain from their habitat.
140. What is the smallest unit of organization in an ecosystem? Give one example from the diagram.
141. Describe one of the prairie dog’s adaptations and how it helps the prairie dog to survive.
142. What level of ecological organization do all of the owls in a certain area represent?
143. Is the prairie soil a biotic factor or an abiotic factor? Explain your answer.
144. Describe three factors that could limit the growth of the prairie dog population.
Use the diagram to answer each question.
145. How was the pheasant population changing at Point A?
146. Which letter marks the peak of the pheasant population?
147. What happened to the pheasant population between Point B and Point C?
148. What are some possible explanations for the change in pheasant population between Point B and Point C?
149. In 1990, a large resort hotel was built on the island where these pheasants live. Explain how this might have
affected the pheasant population.
150. What was the population density of pheasants in 1968, 1976, and 1990?
Environment and Ecology Final Exam Review
Answer Section
COMPLETION
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decomposers
consumer
energy pyramid
highest
top
producer
first-level
first level
condensation
evaporation
nitrogen fixation
carbon dioxide
continental drift
climate
desert
permafrost
climates
combustion
steam
hydrocarbons
oil
petroleum
oil
refinery
solar cells
mirrors
geothermal
biomass
neutron
chain reaction
fission
nuclear fission
meltdown
conservation
efficiency
fans
open windows
recycling
solar
used up
gone
36.
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78.
empty
development
land reclamation
composting
municipal solid waste
reuse
toxic
short-term
short term
bedrock
radon
ultraviolet
chlorofluorocarbons
greenhouse effect
ice
drought
heat
technology
primary
acid rain
ozone
pollutants
pollution
air pollution
renewable
environmental science
benefits
costs
renewable
sustainable yield
niches
economic
keystone species
legal
habitat preservation
genes
medicines
drugs
rain forests
poaching
chemicals
habitat
ecosystem
community
abiotic
water
ecologists
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90.
sampling
birth
limiting
space
adaptation
parasitism
symbiosis
competition
commensalism
host
ecology
secondary
SHORT ANSWER
91. The grasses, trees, cattails, and other plants are all producers.
92. The bear, squirrel, fish, frog, insect [or dragonfly], and lizard are all consumers.
93. Since the other members of the ecosystem cannot make their own food, they would have to leave the area or
they would starve.
94. Answers may vary. Possible answers include: plant  dragonfly  lizard; plant  insect  fish  bear.
95. about 10 percent
96. So much energy is lost at each level of the food pyramid that there is not enough energy to support very many
third-level consumers.
97. Number 8 (nitrogen-fixing bacteria)
98. Number 7 (nitrogen compounds)
99. Nitrogen-fixing bacteria, 8, convert free nitrogen gas into nitrogen compounds. Bacteria that are decomposers,
5, recycle nitrogen compounds in the soil by breaking down animal wastes and dead plants and animals.
Other bacteria, 3, break down nitrogen compounds and release free nitrogen to the air.
100. Animals eat plants and obtain the nitrogen compounds they need to make certain body chemicals. Animal
wastes and dead animals and plants are broken down by bacteria to release nitrogen compounds back into the
soil.
101. Number 5 (decomposers)
102. Nitrogen-fixing bacteria live in nodules, lumps on the roots of legume plants.
103. It is a control rod. It is made of cadmium.
104. Part A is a cadmium control rod used to control the speed of fission reactions. It absorbs the neutrons that
split the U-235 nuclei. This slows down the fission process.
105. It is a fuel rod usually made of uranium-235; it undergoes nuclear fission.
106. A pipe carrying hot water from the reactor enters the heat exchanger. Its heat causes water in the heat
exchanger to boil, forming steam. At the same time the water inside the pipe cools off and is returned to the
reactor vessel.
107. B; nuclear fission reactions
108. The steam turns the blades of a turbine, which is connected to a generator that produces an electric current.
109. coal, petroleum, and natural gas
110. hydroelectric and possibly “other”
111. coal, at 59.3 percent
112. Petroleum and coal produce the most; hydroelectric and nuclear produce the least.
113. nuclear fission
114. Answers may vary, but students may predict that the hydroelectric, “other,” and nuclear wedges will be
bigger, and that the fossil fuel wedges will be smaller because there will be more conservation/less
availability of nonrenewable fossil fuels.
115. Sample answer: Nitrogen oxide and sulfur oxide gases emitted by coal-burning factories or power plants mix
with water vapor in the air to form nitric and sulfuric acid. Precipitation carrying these dissolved acids is
called acid rain.
116. Non-diesel vehicles release 295 times more emissions than diesel vehicles (59/0.2).
117. human activities: diesel and non-diesel motor vehicles; aircraft, railroad, boats; solid waste disposal;
industrial; and agricultural burning; possibly natural: forest fires and other
118. Answers will vary but should be two ways to reduce emissions from motor vehicles, such as carpooling,
riding bicycles, walking, using public transportation, requiring the use of cleaner fuel, and requiring motor
vehicles to have better emission-control systems.
119. 17.9 percent
120. 63.8 percent
121. water vapor and carbon dioxide
122. Heat trapped by greenhouse gases.
123. The theory of global warming states that the increase in carbon dioxide in the atmosphere is causing the
greenhouse effect to grow stronger. As more heat is trapped near Earth’s surface, Earth’s average temperature
is rising.
124. industries and power plants that burn fossil fuels such as coal and oil
125. Possible answers include melting of the Antarctic ice cap, a rise in ocean levels, changes in climate patterns,
more severe storms, and changes in where crops are grown.
126. sunlight (or energy from the sun)
127. They decreased.
128. Eggs with thin shells are more vulnerable to breakage and attack by predators. As fewer eggs hatch, bird
populations will decrease.
129. Sample answers: The birds could have eaten plants covered with DDT. DDT sprayed on the land could also
be washed by rainfall into lakes and rivers. The DDT could then get into the bodies of the fish eaten by the
birds.
130. Species A
131. It increased. After DDT was banned, the birds did not take as much DDT into their bodies.
132. No; some DDT might have remained in the environment even after it was banned in 1973.
133. It has increased dramatically.
134. about 130 years
135. about 9 years
136. Beginning around 1650, improvements in medicine, agriculture, and waste disposal enabled people to live
longer.
137. As the human population grows, the demand for natural resources also grows.
138. Answers may vary but should fall between 6 and 7 billion.
139. The prairie dogs obtain shelter by digging tunnels in the ground and food by eating the grass.
140. The smallest unit of organization in an ecosystem is a single organism. The snake is an example from the
diagram. All other organisms appear as populations in the diagram.
141. Answers may vary. One example is the prairie dog’s claws, which allow it to dig tunnels for shelter. Another
example is the prairie dog’s ability to bark, which allows it to warn other prairie dogs that a predator is
nearby.
142. All of the owls in a certain area represent a population.
143. Soil is an abiotic factor because it is not alive.
144. Populations can be limited by food, space, and weather conditions. The prairie dogs might run out of grass to
eat or suitable land to dig tunnels in. A storm could cause a flood that would destroy some of the prairie dogs’
tunnels.
145. It was increasing.
146. B
147. It decreased.
148. Answers will vary but might include a lack of food for the population, a natural disaster, human interactions
causing more deaths, or a lack of nesting space causing fewer births.
149. When the hotel was built, living space for the pheasants probably decreased. Their population probably
decreased.
150. Approximately 15 pheasants per square kilometer in 1968, 50 per square kilometer in 1976, and 38 per square
kilometer in 1990.