1409 Take Home Exam
Chapter 45 - 49
CHAPTER 45 POPULATION ECOLOGY
1. Ecological interactions involve
a. populations. b. communities. c. ecosystems. d. the biosphere. e. all of these
2. The total number of individuals that actually or potentially contribute to the gene pool defines the population’s
a. distribution. b. growth. c. birth rate. d. size. e. age structure.
3. The average number of individuals of the same species per unit of area or volume at a given time is the population’s
a. distribution. b. carrying capacity. c. density. d. size. e. birth rate.
4. Which of the following is NOT true regarding factors that affect the dispersion of organisms in nature?
a. Most environmental resources are randomly distributed.
b. Biological conditions tend to be nonuniform.
c. Dispersal of offspring is often limited or controlled by environmental factors.
d. The development of societies in some populations controls distribution.
e. Every species is adapted to specific environmental conditions.
5. Random dispersion of individuals in a population occurs when habitat conditions are _____, resource availability is _____, and
individuals or pairs of individuals _____ one another.
a. random; scarce; either attract or avoid
b. clumped; fairly steady; neither attract nor avoid
c. nearly uniform; random; neither attract nor avoid
d. nearly uniform; fairly steady; neither attract nor avoid
e. clumped; scarce; either attract or avoid
6. Which of the following is NOT true regarding population counts?
a. A full population count is usually impractical.
b. Ecologists estimate a population’s total density from a sample of the population.
c. Sampling within quadrats is particularly useful for most populations of migrating animals.
d. A full population count is possible for large animals in small areas.
e. Capture-recapture methods are used to estimate the population’s size of species that do not “stay put.”
7. The accuracy of the capture-recapture methods depends on all of the following EXCEPT that
a. marked individuals are recaptured at random. b. unmarked individuals are captured at random.
c. none of the marked individuals are overlooked. d. no marked individual dies or departs during the study.
e. no new individuals are produced during the study.
8. What concept expresses the growth rate of a given population?
a. doubling time b. population density c. population size
d. carrying capacity e. biotic potential
9. The net reproduction per individual per unit time (r) is _____ per mouse per month in a population of 1,000 mice where 500 mice
are born and 400 mice die monthly.
a. 0.1 b. 0.2 c. 0.3 d. 0.4 e. 0.5
10. Which of the following is NOT true regarding biotic potential? It
a. varies from one species to another. b. is related to the timing of the first reproduction.
c. is related to the frequency of reproduction. d. is related to the number of offspring produced.
e. increases as population density increases
11. As population density increases, the chance of _____ also increases.
a. parasitism b. disease c. predation d. competition e. all of these
12. The plants that formed the basis for the development of agriculture and the spread of civilization are members of the _____ family.
a. grass b. legume c. potato d. citrus e. herb
13. If a population has an r = 0.02, which of the following statements must be true?
a. Two of every 100 individuals will give birth over the course of a year.
b. Two individuals will be born for every 100 individuals in the population over the course of a year.
c. Births will exceed deaths by 2 percent over the course of a year.
d. The number of individuals added to the population will be 2 percent greater than the number of individuals removed
from the population over the course of a year.
e. none of these
14. Which of the following is NOT true for a population growing exponentially?
a. The number of individuals added to the population in a year is greater than it was the previous year.
b. The population growth rate increases year after year.
c. Its r remains constant in the short-run.
d. The doubling time remains constant.
e. all of these
15. Which of the following statements is NOT true regarding population-limiting factors?
a. The number of limiting factors may be extensive.
b. A combination of limiting factors is required to inhibit population growth.
c. Rapidly growing populations are affected by limiting factors.
d. Small populations are affected by limiting factors.
e. Slow-growing populations are affected by limiting factors.
16. A cohort is
a. a group of newborn individuals of the same species.
b. any member of the same species. c. a group of individuals with the same parents.
d. a group of individuals of the same sex. e. any group of closely related individuals.
17. Type II survivorship curves
a. are characteristic of humans and elephants.
b. indicate a fairly constant rate of death at all ages.
c. indicate a high mortality rate in the very young.
d. are characteristic of species in which most individuals live a relatively long life and die of old age.
e. are typical of species with high biotic potentials.
18. Which of the following is NOT true regarding guppies of the species Poecilia reticulata?
a. Males are generally smaller than the females.
b. Males are more brightly colored than the females.
c. Males continue growing after reaching sexual maturity.
d. The male’s colors serve as visual signals for mating.
e. They have complex mating rituals.
19. The leading cause of human deaths is
a. heart disease. b. cancer. c. malnutrition and starvation.
d. war. e. accidents.
20.Countries expected to show the most growth in decreasing order are
a. China > India > Pakistan > Nigeria > Bangladesh > Indonesia.
b. China > Pakistan > India > Nigeria > Bangladesh > Indonesia.
c. India > China > Pakistan > Nigeria > Bangladesh > Indonesia.
d. India > China > Pakistan > Bangladesh > Nigeria > Indonesia.
e. India > China > Pakistan > Bangladesh > Indonesia > Nigeria.
21. Insects that lay their eggs in and whose larvae subsequently feed on the soft tissues of the host are
a. typical parasites. b. commensals. c. parasitoids. d. predators. e. cannibalistic.
Chapter 45 Population Ecology 2
22. Which of the following would be more likely to affect an animal’s habitat than its niche?
a. rainfall b. prey abundance c. predators d. defense mechanisms e. competitors
23. The range of all factors that influence whether a species can obtain resources essential for survival and reproduction is its
a. habitat. b. niche. c. carrying capacity. d. ecosystem. e. community.
24. In facultative mutualism
a. both species are animals.
b. the interaction is helpful but not essential for survival.
c. one species is an animal and the other a fungus.
d. each species must have access to the other to complete its life cycle.
e. none of these
25.Which of the following associations is NOT an example of obligatory mutualism?
a. mycorrhiza and plant roots b. yucca plants and yucca moths
c. ants and aphids d. lichens e. all of these
26. In mycorrhizal associations
a. fungal hyphae penetrate plant root cells or form mats around them.
b. the plant takes some minerals from the fungus.
c. the fungus takes some sugars from the plant.
d. the fungus depends upon the plant for its reproductive success.
e. all of these
27. In most cases of interspecific interference competition, the inferior competitor displaced from an area of niche overlap is
a. smaller. b. slower.
c. more specialized in its niche requirements. d. less specialized in its niche requirements.
e. taxonomically distant.
28. Gause’s experiments with Paramecium growing in test tubes demonstrated that
a. organisms with similar niches evolve enough to survive in different niches.
b. organisms with slightly different nutritional requirements change to become exclusive competitors.
c. organisms with similar nutritional requirements may compete to the point of extinction.
d. organisms with slightly different nutritional requirements change to become exclusive competitors, and organisms with
similar nutritional requirements may compete to the point of extinction.
e. organisms with similar niches evolve enough to survive in different niches, and organisms with similar nutritional
requirements may compete to the point of extinction.
29. Which of the following is(are) true about predator–prey coevolution?
a. Each species exerts selection pressure on the other.
b. Predators are selective agents that favor improved prey defenses.
c. Prey with better defenses are selective agents that favor better predator hunting skills.
d. all of these
e. none of these
30. Humans hunt the black rhinoceros, which is rapidly approaching extinction as a result of this predation. What accounts for the
absence of stable coexistence between the two species?
a. Predator and prey have not coevolved.
b. Human predation is not necessarily density-dependent.
c. The prey reproductive rate is greater than that of the predator.
d. Predator and prey have not coevolved and human predation is not necessarily density-dependent.
e. Predator and prey have not coevolved, human predation is not necessarily density-dependent, and the prey reproductive
rate is greater than that of the predator.
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31. Which of the following is NOT a common result of predation?
a. The level of the predator population is maintained near or below the carrying capacity.
b. Both predator and prey undergo selection leading to coevolution.
c. The predator or prey becomes extinct.
d. The level of the prey population is maintained near or below the carrying capacity of the environment.
e. all of these
32. Ladybugs are effective natural control agents against pest insects, but as gardeners soon find out, ladybugs do not reduce pest
populations to zero because
a. they can’t fly to find pests on nearby plants. b. of their very selective feeding habits.
c. to do so jeopardizes their own existence. d. they don’t live long enough.
e. their reproductive capacity is nonexistent.
33. Cockroaches will overrun a kitchen until _____ without intervention by humans.
a. the carrying capacity is reached b. predators attack
c. parasites invade the roaches’ bodies d. density-independent factors such as cold intervene
e. any of these
34.What conclusion can be drawn from research on abundance cycles of Canadian lynx and snowshoe hare?
a. A simple predator–prey model explains the results.
b. A simple plant–herbivore model explains the results.
c. Raptor activity has no effect on the outcome.
d. Complex variables are involved.
e. Manipulation of experimental plots stopped cyclic changes in population densities.
35. Which of the following statements about predation is(are) true?
a. It can result in an increase in species diversity.
b. It can cause extinction of a prey species.
c. It can prevent extinction of a prey species.
d. It can result in an increase in species diversity, and it can cause extinction of a prey species.
e. It can result in an increase in species diversity, it can cause extinction of a prey species, and it can prevent extinction of
a prey species.
36. Which of the following statements is NOT generally characteristic of parasites?
a. They are specialists and usually are able to affect only one variety of hosts.
b. They inflict serious injury and kill their hosts.
c. Some reside inside their hosts, whereas others live outside their hosts.
d. Their host may be a plant as well as an animal.
e. Some require more than one host to complete the life cycle.
37. During the process of community succession, according to the traditional view,
a. the total biomass remains constant.
b. there are increasing possibilities for resource partitioning.
c. the pioneer community gives way quickly to the climax community, followed by a succession of more diverse arrays of
d. nutrients cycle more rapidly with time.
e. all of these
38. Pioneer plant species are usually characterized by
a. small size.
b. efficient dispersal mechanisms.
c. slow maturation.
d. small size and efficient dispersal mechanisms.
e. small size, efficient dispersal mechanisms, and slow maturation.
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39. Which of the following statements is false about pioneer species?
a. They have wide ranges of tolerance.
b. Many are mutualistic with nitrogen-fixing bacteria.
c. They remain permanent residents of the community.
d. They include lichens and plants with short life cycles.
e. They are often small annuals with an abundance of easily dispersed seeds.
40. Which of the following is(are) among the most deleterious exotic invaders?
a. Oryctolagus cuniculus in Australia b. Pueraria montana in the United States
c. Caulerpa taxifolia strain in the Mediterranean d. Bufo marinus worldwide
e. all of these
CHAPTER 47 ECOSYSTEMS
41. Which of the following combinations of organisms can survive in isolation from other forms of life?
a. producers and decomposers b. producers and carnivores
c. carnivores and decomposers d. carnivores and parasites e. producers and parasites
42. If the _____ in an ecosystem die, wastes will accumulate and most nutrients will stop cycling.
a. plants and animals b. bacteria and fungi
c. roundworms and earthworms d. phytoplankton and zooplankton
e. algae and lichens
43. Chemoautrophic organisms are
a. primary consumers. b. secondary consumers. c. tertiary consumers.
d. primary producers. e. secondary producers.
44. Primary carnivores are
a. tertiary consumers in the second trophic level. b.secondary consumers in the third trophic level.
c. secondary consumers in the second trophic level. d. tertiary consumers in the fourth trophic level.
e. secondary consumers in the first trophic level.
45. A secondary carnivore may eat
a. herbivores. b. primary producers. c. primary carnivores.
d. second trophic level consumers. e. any of these
46. Plants store about _____ percent of the energy they capture from the sun.
a. 20 b. 30 c. 40 d. 50 e. 60
47. Ecologists determined that, regardless of the richness of the ecosystem, energy passes through no more than _____ trophic levels.
a. one or two b. two or three c. three or four d. four or five e. five or six
48. A third level consumer may eat
a. herbivores. b. primary producers. c. primary carnivores.
d. second trophic level organisms. e. any of these
49. Which of the following represents energy flow in a grazing food web?
a. producers >>> detritivores >>> decomposers
b. producers >>> decomposers >>> detritivores
c. producers >>> herbivores >>> decomposers >>> carnivores
d. producers >>> herbivores >>> carnivores >>> decomposers
e. producers >>> herbivores >>> detritivores >>> carnivores
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50. Energy loss through a detrital food web is _____ that of a grazing web.
a. the same as b. somewhat greater than c. less than
d. about twice e. significantly greater than
51. Biological magnification refers to the _____ at the higher trophic levels.
a. larger size of animals b. greater number of organisms
c. the greater number of species d. accumulation of toxic pollutants in animals
e. all of these
52. Due to its chemical nature, DDT tends to accumulate mainly in _____ tissue.
a. muscle b. nerve c. adipose d. bone e. cartilage
53 The most vulnerable organisms to the effects of DDT are
a. producers. b. herbivores. c. primary carnivores. d. decomposers. e. top carnivores.
54. The difference between gross primary productivity and net primary productivity is the
a. amount of sunlight reflected by plants. b. rate of photosynthesis of autotrophs.
c. rate of energy utilization by autotrophs. d. rate of consumption of autotrophs by herbivores.
e. net ecological productivity.
55. The _____ the conditions are, the _____ new growth plants add in a given season, and the _____ the primary productivity.
a. more conducive; less; lower b. harsher; more; greater c. harsher; less; lower
d. more conducive; more; lower e. harsher; more; lower
56. The pyramid of energy illustrates
a. the first law of thermodynamics.
b. the diminishing of usable energy as it is transferred through an ecosystem.
c. that energy can be recycled.
d. the biological magnification of materials in an ecosystem.
e. the diminishing number of organisms at each trophic level.
57. Assume that an energy pyramid has four levels and also assume that the energy in the producer level is set at 100 percent. What
percent of the energy from the producers do the secondary carnivores obtain?
a. 0.001 to 0.655 b. 0.022 to 0.410 c. 0.360 to 2.560 d. 6 to 16 e. 1 to 10
58. Which of the following statements is false?
a. Ecologists use models to represent relationships between biogeochemical cycles and most ecosystems.
b. The physical environment has virtually no reservoirs for most elements.
c. Inputs from the physical environment and recycling made possible by decomposers and detritivores maintain the
nutrient reserves in an ecosystem.
d. In most major ecosystems, the amount of nutrients that is cycled within the ecosystem is greater than the amount
entering or leaving the ecosystem in a given year.
e. Once elements are in the biological parts of the biogeochemical cycles, they are unlikely to leave until the organism
59. Most of the water on the earth’s surface is not fit for human consumption because it contains a high concentration of
a. microbial contaminants. b. salt. c. heavy metals. d. pesticides. e. mineral ions.
60. All of the following are true regarding the global water crisis EXCEPT that
a. groundwater overdrafts are high in the United States.
b. no city dumps untreated sewage into coastal waters.
c. the United States and Mexico have squabbled over water allotments.
d. the amount of fresh water available for everyone will soon be as much as 66 percent less than it was in the 1970s.
e. mineral nutrients such as phosphates may be freshwater pollutants.
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CHAPTER 48 THE BIOSPHERE
61. The primary reason for climatic differences from one part of the world to another is
a. differences in atmospheric pressures. b. differential absorption of solar energy.
c. prevailing wind currents. d. differences in humidity.
e. variation in cloud cover.
62. The amount of solar energy that any spot on the surface of the earth receives is affected by the
a. photoperiod or duration of light. b. angle at which the sun strikes the earth.
c. amount of atmosphere above the spot. d. particulate matter and pollution in the atmosphere.
e. all of these
63. Which of the following factors does NOT appear to be correlated with a decrease in atmospheric ozone?
a. suppression of the immune system b. phytoplankton kills
c. increased incidence of skin cancers d. decreased levels of oxygen in the ozone layer
e. increased incidence of cataracts
64. The ozone layer is known to thin above what region(s)?
a. both poles b. the equator
c. 60 degrees north and south latitudes d. 30 degrees north and south latitudes e. all of these
65. Uses of chlorofluorocarbons (CFCs) include all EXCEPT which of the following?
a. gasoline additives b. aerosol propellants
c. refrigeration coolants d. manufacture of plastic foam e. components of solvents
66. Even if chlorofluorocarbon production is phased out by 2010, it will be at least _____ years before the ozone layer fully recovers.
a. 10 b. 30 c. 50 d. 75 e. 100
67. Thermal inversions
a. enhance the movement of pollutants into the upper reaches of the atmosphere.
b. are characteristic of the atmosphere over extensive stretches of land, such as prairies.
c. occur as temperature changes between daytime and nighttime.
d. occur when warm air is trapped between layers of cool air.
e. occur when warm air rises through layers of cooler air.
68. Which of the following factors is NOT characteristic of a city plagued primarily by industrial smog?
a. high concentration of sulfur oxides b. dependence on fossil fuel for manufacturing
c. cold, wet winters d. high concentration of nitrogen oxides
e. coal-burning power plants
69. What results when nitrogen dioxide and hydrocarbons react in the presence of sunlight?
a. photochemical smog b. industrial smog c. a thermal inversion
d. depletions of the ozone layer e. any of these
70. Ocean currents flow in response to _____; their direction is an outcome of the earth’s rotation and _____, causing a _____ rotation
in the Northern Hemisphere and a _____ rotation in the Southern Hemisphere.
a. gravity; topography; counterclockwise; clockwise b. topography; gravity; clockwise; counterclockwise
c. temperature; topography; clockwise; counterclockwise d. winds; topography; clockwise; counterclockwise
e. winds; gravity; clockwise; counterclockwise
71. Which is NOT a biogeographic realm?
a. Palearctic b. Ethiopian c. Equatorial d. Oriental e. Australian
72. Similarity of one biome to another is mostly due to
a. altitude only. b. latitude only. c. temperature only. d. altitude and latitude. e. water availability.
73. The biome most in danger of desertification is the
a. desert. b. grassland. c. deciduous forest. d. tropical rain forest. e. taiga.
74. Which of the following areas is NOT characterized by chaparral vegetation?
a. California coast b. central Chile c. Cuba
d. southern tip of Africa e. land near the Mediterranean Sea
75. Fire in the dry shrublands does not kill the small bushy plants most probably because
a. these plants have a tough protective bark.
b. their leaves are very heavy and wet.
c. they can resprout from root crowns.
d. the Forest Service puts the fires out quickly.
e. the fires burn the taller plants and burn out before reaching ground level.
76. Grassland biomes around the earth vary in several ways, but the chief factor causing the variation is the
a. amount of rainfall. b. vegetation. c. oil type.
d. animal life. e. prevailing wind pattern.
77. Away from equatorial forests, the _____ season _____ and broadleaf forests are _____ complex.
a. dry; decreases; less b. wet; grows longer; less c. dry; grows longer; less
d. wet; grows longer; more e. dry; decreases; more
78. Evergreen trees are found in the
a. tropics. b. subtropics. c. taiga. d. boreal forests. e. all of these
79. Arctic and alpine tundras have all of the following in common EXCEPT
a. low moisture. b. permafrost. c. minimal plant life.
d. cold temperatures. e. nutrient-poor soils.
80. Subsistence agriculture does not utilize
a. human labor. b. natural fertilizers. c. available soil.
d. synthetic fertilizers. e. animal labor.
81. Africanized bees _____ than European honeybees.
a. make less honey
b. respond more quickly to perceived threats
c. are more aggressive stingers
d. are more likely to abandon their colony after being disturbed
e. all of these
82. Recent studies in humans have shown there is a close relationship between poor nutrition and poor learning ability. These studies
a. there is only a minor genetic component to learned behavior. b. behavior is modified by the environment.
c. learning is adaptive. d. learning is instinctive.
e. learning involves fixed action patterns.
83. Which of the following concerning instinctive behavior is false?
a. Instinctive behavior does not have to be learned. b. Behavior in newborn animals is mainly instinctive.
c. It cannot be modified by the environment. d. Instinct is recognized by its stereotyped nature.
e. Sign stimuli evoke fixed action patterns.
84. Learned behavior is recognizable by the _____ the animal makes in its responses.
a. fixed action patterns b. changes c. stereotyping d. repetitions e. false starts
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85. Studies of _____ in young animals could lend support for arguments that human parents and babies need to spend as much time
together as possible.
a. conditioning b. imprinting c. habituation d. insight learning e. instinctive behavior
86. Which of the following is false?
a. Imprinting can be learned only during a limited time span.
b. Bird song can be learned only during a limited time span.
c. For a bird to be able to sing the song of its species it must have heard it.
d. Instinctive behavior has adaptive value.
e. In explaining an adaptive behavioral trait, it is better to use an approach based upon a species benefiting rather than an
87. The example(s) that illustrate(s) natural selection acting on behavioral traits that benefit individuals include(s)
a. the effect of oxytocin on vole reproductive behavior.
b. the different responses of young coastal and inland garter snakes to banana slugs.
c. courtship behavior in sage grouses.
d. the nest-decorating behavior of starlings.
e. all of these
88. Which of the following statements is false?
a. Behavior patterns are inherited.
b. Instinctive behavior involves a complete response to a sign stimulus the first time it is encountered.
c. Behavior evolves as a result of natural selection.
d. Reproductive success is responsible for perpetuating behavior patterns.
e. The mechanisms underlying instinctive and learned behavior are the same.
89. During aggressive encounters between members of the same species,
a. the strong members are always victorious.
b. the invader into a territory is able to replace the current resident of the territory unless he has already mated.
c. opponents usually settle the dispute without bloodshed.
d. a fight to the death occurs, with the one higher in the pecking order being successful more often.
e. none of these
90. Which of the following communication signals is mismatched?
a. tactile; honeybees b. acoustical; frogs c. visual; baboons
d. chemical; termites and honeybees e. chemical; albatrosses
91. Which of the following statements is false?
a. Males often help with parenting in cases where females compete over males.
b. There is often a ready-made harem in cases where males compete for access to females.
c. Sexual selection through competition for mates leads to evolutionary change.
d. Reproductive success is based upon the same criteria for both sexes.
e. Males that do not have territorial or sexual status sometimes employ strategies that allow them
92. The presence of the strongest competitors in the center of a group of animals may qualify the group for status as a(n)
a. altruistic society. b. selfish herd. c. kin group. d. dominance hierarchy. e. sexual selection society.
93. Which of the following features of territoriality is NOT an advantage?
a. Territorial behavior enables a male to attract a mate.
b. Territoriality requires a male to place himself at risk.
c. Territoriality ensures an adequate food supply.
d. Territoriality limits the size of a population and its impact upon its environment.
e. Territoriality may reduce the fighting between mature males.
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94. All EXCEPT which of the following are disadvantages to sociality?
a. predator avoidance b. cannibalism c. competition for food
d. contagious diseases e. parasite infestation
95. Whatever the motivation of self-sacrificing behavior on the part of nonhuman animals is, we know it is NOT
a. genetic. b. the result of selection.
c. derived from conscious reason d. a result of dominance hierarchy.
e. related to species-survival strategies.
96. Which of the following statements is false?
a. A communication signal has benefits for both the sender and the receiver.
b. Under some circumstances, solitary individuals may leave more descendants than do social ones.
c. Social animals must exhibit altruism.
d. Not every environment favors the evolution of social life.
e. Altruism may mean sacrificing personal reproductive success in order to help others in the population.
97. Researchers attempt to explain the persistence of altruism by the theory of
a. self-sacrificing behavior. b. dominance hierarchy. c. social behavior.
d. indirect selection. e. sexual selection.
98. If an individual for whatever reason cannot pass on its genes to offspring, the best alternative is to show altruism to
a. relatives. b. strangers. c. neighbors. d. other species. e. competitors.
99. Which of the following statements is false?
a. Humans may exhibit altruistic behavior.
b. Social life may increase the risk for disease and competition.
c. Social species are more highly evolved.
d. Natural selection acts to favor sterility in social communities where sterility is an advantage.
e. Indirect selection is based upon altruism, which in its extreme expression may lead to sterility.
100. From a species standpoint, sex in chimpanzees is
a. a major force in the social life of the troop.
b. responsible for developing social alliances.
c. a way for females to benefit from male attention.
d. a major force in the social life of the troop and responsible for developing social alliances.
e. a major force in the social life of the troop, responsible for developing social alliances, and a way for females to benefit
from male attention.
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