Exam

Name___________________________________

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
 
1)  Which of the following statements best describes the interaction between fire and ecosystems? 1) ______
  A)  Many kinds of plants and plant communities have adapted to frequent fires.
  B)  Fire is unnatural in ecosystems and should be prevented.
  C)  The prevention of forest fires has allowed more productive and stable plant communities to develop.
  D)  Chaparral communities have evolved to the extent that they rarely burn.
  E)  The chance of fire in a given ecosystem is highly predictable over the short term.

2)  During exponential growth, a population always 2) ______
  A)  grows at its maximum per capita rate.
  B)  quickly reaches its carrying capacity.
  C)  cycles through time.
  D)  grows by thousands of individuals.
  E)  loses some individuals to emigration.

3)  Zoonotic disease 3) ______
  A)  can only be spread from animals to humans through direct contact.
  B)  is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector.
  C)  is too specific to study at the community level, and studies of zoonotic pathogens are relegated to organismal biology.
  D)  describes sub-organismal pathogens such as viruses, viroids, and prions.
  E)  can only be transferred from animals to humans by means of an intermediate host.

4)  Which of the following is a tertiary consumer? 4) ______
  A)  snake
  B)  grasshopper
  C)  grass
  D)  shrew
  E)  hawk

5)  After a disturbance, natural recovery of a biological community is most strongly influenced by 5) ______
  A)  the availability of water nearby.
  B)  the spatial scale of the disturbance.
  C)  whether the site is in a temperate or tropical area.
  D)  whether the disturbance has been caused by humans or by a natural agent.
  E)  the season in which the disturbance occurred.

6)  A population of strictly monogamous swans consists of 40 males and 10 females. What is the effective population size (Ne) for this population? 6) ______
  A)  50
  B)  20
  C)  32
  D)  10
  E)  40

Use the information below about quail habitats to answer the following questions.


Figure 56.1

7)  Assuming that only one quail can occupy a habitat where all cover requirements are met, what is the maximum number of quail that could inhabit any of the hypothetical plots shown? 7) ______
  A)  4
  B)  9
  C)  6
  D)  2
  E)  1

8)  The term "biotic boundary" refers to the 8) ______
  A)  distribution of an organism.
  B)  range where a species used to live, but no longer does.
  C)  area needed to sustain a population.
  D)  area that an animal defends as its territory.
  E)  home range of an animal.

9)  A movement corridor 9) ______
  A)  is a path used by migratory animals when they move to their wintering locales.
  B)  is always beneficial to a species.
  C)  is the path most commonly used by an animal within its home range.
  D)  unites otherwise isolated patches of quality habitat.
  E)  is always some natural component of the environment.

10)  Overexploitation encourages extinction and is most likely to affect 10) ______
  A)  animals that occupy a broad ecological niche.
  B)  most organisms that live in the oceans.
  C)  large animals with low intrinsic reproductive rates.
  D)  terrestrial organisms more than aquatic organisms.
  E)  edge-adapted species.

11)  Which of the following species was driven to extinction by overexploitation by hunters/fishermen? 11) ______
  A)  the great auk
  B)  African elephant
  C)  American bison
  D)  flying foxes
  E)  North American bluefin tuna

12)  Of the following statements about protected areas that have been established to preserve biodiversity, which one is not correct? 12) ______
  A)  Management of a protected area should be coordinated with management of the land surrounding the area.
  B)  National parks are one of many types of protected area.
  C)  It is especially important to protect biodiversity hot spots.
  D)  About 25% of Earth's land area is now protected.
  E)  Most protected areas are too small to protect species.

13)  Which of the following life history traits can potentially influence effective population size (Ne)? 13) ______
  A)  genetic relatedness among individuals in a population
  B)  maturation age
  C)  family and population size
  D)  gene flow between geographically separated populations
  E)  A, B, C and D are correct.

14)  What term did E. O. Wilson coin for our innate appreciation of wild environments and living organisms? 14) ______
  A)  landscape ecology
  B)  bioremediation
  C)  bioethics
  D)  biophilia
  E)  biophobia

15)  Which of the following is true about the current research about forest fragmentation? 15) ______
  A)  Harvesting timber that results in forest fragmentation results in less soil erosion.
  B)  The disturbance of timber extraction causes the species diversity to increase because of the new habitats created.
  C)  Fragmented forests support a lesser biodiversity because the forested-adapted species leave, and only the edge and open-field species can occupy fragmented forests.
  D)  Fragmented forests are the goal of conservation biologists who design wildlife preserves.
  E)  Fragmented forests support a greater biodiversity because they result in the combination of forest-edge species and forest interior species.

16)  Review the formula for effective population size. Imagine a population of 1,000 small rodents. Of these, 300 are breeding females, 300 are breeding males, and 400 are nonbreeding juveniles. What is the effective population size? 16) ______
  A)  400
  B)  300
  C)  600
  D)  1,200
  E)  1,000

17)  Which of the following would a landscape ecologist consider in designing a nature reserve? 17) ______
  A)  patterns of landscape use by humans
  B)  nature viewing sites
  C)  human economic concerns
  D)  possible edge effects related to human activities
  E)  A, B, C, and D are all correct

18)  Which of the following conditions is the most likely indicator of a population in an extinction vortex? 18) ______
  A)  The population is geographically divided into smaller populations.
  B)  The effective population size of the species falls below 500.
  C)  The population is no longer connected by corridors.
  D)  The species is found only in small pockets of its former range
  E)  Genetic measurements indicate a continuing loss of genetic variation.

19)  Which of the following would be research in which a conservation biologist would be involved? 19) ______
  A)  population ecology of grizzly bears in Yellowstone National Park
  B)  reestablishing whooping cranes in their former breeding grounds in North Dakota
  C)  the effect of protection programs on the recovery of the North Atlantic cod fishery
  D)  the effects of hunting on white-tailed deer in Vermont
  E)  studying species diversity and interaction in the Florida Everglades, past and present

20)  Which of the following would be considered an example of bioremediation? 20) ______
  A)  adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability
  B)  reconfiguring the channel of a river
  C)  identifying a new biodiversity hot spot
  D)  adding seeds of a chromium-accumulating plant to soil contaminated by chromium
  E)  using a bulldozer to regrade a strip mine

21)  Human use of prokaryotic organisms to help detoxify a polluted wetland would be an example of 21) ______
  A)  bioremediation.
  B)  biological control.
  C)  population viability analysis.
  D)  keystone species introduction.
  E)  ecosystem augmentation.

Use what you know about ecosystem stability and the information provided in the graph below to answer the following question.
22)  Which community (A-E) would likely be the most "biodiverse"?


22) ______
  A)  A
  B)  B
  C)  C
  D)  D
  E)  E

23)  Of the following, which ecosystem types are the ones that have been impacted by humans the most? 23) ______
  A)  open and benthic ocean
  B)  taiga and second growth forests
  C)  desert and high alpine
  D)  wetland and riparian
  E)  tundra and arctic

24)  The primary difference between the small-population approach (S-PA) and the declining-population approach (D-PA) to biodiversity recovery is 24) ______
  A)  S-PA would investigate and eliminate all of the human impacts on the habitat of the species being studied for recovery.
  B)  D-PA would likely involve the bringing together of individuals from scattered small populations to interbreed to promote genetic diversity.
  C)  D-PA would use recently collected population data to calculate an extinction vortex.
  D)  S-PA is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population's decline.
  E)  S-PA kicks in for conservation biologists when population numbers fall below 500.

25)  For most terrestrial ecosystems, pyramids of numbers, biomass, and energy are essentially the same-they have a broad base and a narrow top. The primary reason for this pattern is that 25) ______
  A)  top carnivores and secondary consumers have a more general diet than primary producers.
  B)  secondary consumers and top carnivores require less energy than producers.
  C)  at each step, energy is lost from the system as a result of keeping the organisms alive.
  D)  biomagnification of toxic materials limits the secondary consumers and top carnivores.
  E)  as matter passes through ecosystems, some of it is lost to the environment.

26)  Which of the following is a consequence of biological magnification? 26) ______
  A)  Populations of top-level predators are generally smaller than populations of primary consumers.
  B)  The amount of biomass in the producer level of an ecosystem decreases if the producer turnover time increases.
  C)  Toxic chemicals in the environment pose greater risk to top-level predators than to primary consumers.
  D)  Only a small portion of the energy captured by producers is transferred to consumers.
  E)  The biomass of producers in an ecosystem is generally higher than the biomass of primary consumers.

27)  Which of the following terms encompasses all of the others? 27) ______
  A)  carnivores
  B)  heterotrophs
  C)  secondary consumers
  D)  primary consumers
  E)  herbivores

28)  Which of the following statements best describes why biologists are currently concerned with global warming and the thawing of permafrost in many areas of the tundra biome? 28) ______
  A)  The thawing process will likely decrease the abundance and diversity of soil-dwelling organisms in tundra habitats.
  B)  Oil and coal deposits will thaw and rise to the surface (because of their lower density) of the tundra, destroying millions of acres of arctic habitat.
  C)  Populations of humans inhabiting the arctic will have to move to more southern latitudes, resulting in increased competition for resources in already densely populated areas.
  D)  The bacterial decomposition of the thawed organic materials on the widespread areas of the tundra will produce large quantities of CO2, which will add to greenhouse gases and exacerbate global warming.
  E)  Migratory species of waterfowl will likely be less successful finding food in thawed tundra, and population numbers will drop dramatically.

29)  Aquatic ecosystems are least likely to be limited by which of the following nutrients? 29) ______
  A)  carbon
  B)  phosphorus
  C)  zinc
  D)  iron
  E)  nitrogen

Use the incomplete diagram below, illustrating some of the steps involved in eutrophication to answer the following questions.


Figure 55.3

30)  What would be a likely entry for box A? 30) ______
  A)  increased temperature
  B)  increased ultraviolet radiation
  C)  increased sunlight
  D)  fertilizers washed into the lake
  E)  elimination of zooplankton

31)  How does phosphorus normally enter ecosystems? 31) ______
  A)  photosynthesis
  B)  cellular respiration
  C)  atmospheric phosphorous dust
  D)  rock weathering
  E)  geological uplifting (subduction and vulcanism)

32)  Which of the following is caused by excessive nutrient runoff into lakes? 32) ______
  A)  biological magnification
  B)  greenhouse effect
  C)  eutrophication
  D)  turnover
  E)  depletion of atmospheric ozone

33)  Many homeowners mow their lawns during the summer and collect the clippings, which are then hauled to the local landfill. Which of the following actions would most benefit the local ecosystem? 33) ______
  A)  Collect the clippings and wash them into the nearest storm sewer that feeds into the local lake.
  B)  Either collect the clippings and add them to a compost pile, or don't collect the clippings and let them decompose into the lawn.
  C)  Dig up the lawn and cover the yard with asphalt.
  D)  Collect the lawn clippings and burn them.
  E)  Allow sheep to graze the lawn and then collect the sheep's feces to be delivered to the landfill.

34)  Trophic efficiency is 34) ______
  A)  a measure of how nutrients are cycled from one trophic level to the next.
  B)  about 90% in most cosystems
  C)  the ratio of net secondary production to assimilation of primary production.
  D)  the percentage of production transferred from one trophic level to the next.
  E)  usually greater than production efficiencies.

35)  The main cause of the increase in the amount of CO2 in Earth's atmosphere over the past 150 years is 35) ______
  A)  increased worldwide primary production.
  B)  additional respiration by the rapidly growing human population.
  C)  the burning of larger amounts of wood and fossil fuels.
  D)  an increase in the amount of infrared radiation absorbed by the atmosphere.
  E)  increased worldwide standing crop.

36)  Agricultural lands frequently require nutritional supplementation because 36) ______
  A)  the prairies that comprise good agricultural land tend to be nutrient-poor.
  B)  cultivation of agricultural lands inhibits the decomposition of organic matter.
  C)  the nutrients that enter the plants are not returned to the soil on lands where they are harvested.
  D)  grains raised for feed must be fortified, and thus require additional nutrients.
  E)  nitrogen-fixing bacteria and detrivores do not cycle nutrients as effectively as they do on wild lands.

37)  Which of the following has the greatest effect on the rate of chemical cycling in an ecosystem? 37) ______
  A)  the trophic efficiency of the ecosystem
  B)  the rate of decomposition in the ecosystem
  C)  the ecosystem's rate of primary production
  D)  the production efficiency of the ecosystem's consumers
  E)  the location of the nutrient reservoirs in the ecosystem

38)  Which of the following probably contains the highest concentration of toxic pollutants (biological magnification)? 38) ______
  A)  grasshopper
  B)  snake
  C)  grass
  D)  hawk
  E)  shrew

39)  Which of these ecosystems has the lowest net primary production per square meter? 39) ______
  A)  a grassland
  B)  a tropical rain forest
  C)  an open ocean
  D)  a coral reef
  E)  a salt marsh

40)  The difference between net and gross primary productivity would likely be greatest for 40) ______
  A)  phytoplankton in the ocean.
  B)  corn plants in a farmer's field.
  C)  an oak tree in a forest.
  D)  sphagnum moss in a bog.
  E)  prairie grasses.

41)  If the Sun were to suddenly stop providing energy to Earth, most ecosystems would vanish. Which of the following ecosystems would likely survive the longest after this hypothetical disaster? 41) ______
  A)  tundra
  B)  benthic ocean
  C)  grassland
  D)  desert
  E)  tropical rainforest

42)  Which of the following is primarily responsible for limiting the number of trophic levels in most ecosystems? 42) ______
  A)  Nutrient cycles involve both abiotic and biotic components of ecosystems.
  B)  Many primary and higher-order consumers are opportunistic feeders.
  C)  Decomposers compete with higher-order consumers for nutrients and energy.
  D)  Nutrient cycling rates tend to be limited by decomposition.
  E)  Energy transfer between tropic levels is in almost all cases less than 20% efficient.

43)  You have a friend who is wary of environmentalists' claims that global warming could lead to major biological change on Earth. Which of the following statements can you truthfully make in response to your friend's suspicions? 43) ______
  A)  We know that atmospheric carbon dioxide has increased in the last 150 years.
  B)  Global warming could have significant effects on United States agriculture.
  C)  Through measurements and observations, we know that carbon dioxide levels and temperature fluctuations were directly correlated even in prehistoric times.
  D)  Sea levels will likely rise, displacing as much as 50% of the world's human population.
  E)  A, B, C, and D are all correct

44)  According to the equilibrium model of island biogeography, species richness would be greatest on an island that is 44) ______
  A)  small and close to a mainland.
  B)  small and remote.
  C)  large and close to a mainland.
  D)  environmentally homogeneous.
  E)  large and remote.

45)  Which of the following statements is consistent with the principle of competitive exclusion? 45) ______
  A)  Bird species generally do not compete for nesting sites.
  B)  Two species with the same fundamental niche will exclude other competing species.
  C)  Evolution tends to increase competition between related species.
  D)  Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species.
  E)  The density of one competing species will have a positive impact on the population growth of the other competing species.

46)  Which of the following could qualify as a top-down control on a grassland community? 46) ______
  A)  influence of soil nutrients on the abundance of grasses versus wildflowers
  B)  limitation of plant biomass by rainfall amount
  C)  effect of humidity on plant growth rates
  D)  influence of temperature on competition among plants
  E)  effect of grazing intensity by bison on plant species diversity

47)  Which of the following is an example of Batesian mimicry? 47) ______
  A)  an insect that resembles a twig
  B)  a fawn with fur coloring that camouflages it in the forest environment
  C)  a snapping turtle that uses its tongue to mimic a worm, thus attracting fish
  D)  a butterfly that resembles a leaf
  E)  a non-venomous snake that looks like a venomous snake

48)  Which of the following best describes the consequences of White-band disease in Caribbean coral reefs? 48) ______
  A)  Staghorn coral has been decimated by the pathogen, and Elkhorn coral has taken its place.
  B)  Key habitat for lobsters, snappers, and other reef fishes has improved.
  C)  Algal species take the place of the dead coral, and the fish community is dominated by herbivores.
  D)  Other coral species take the place of the affected Staghorn and Elkhorn species.
  E)  Algal species take over and the overall reef diversity increases due to increases in primary productivity.

49)  In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field. A possible factor in this secondary succession was 49) ______
  A)  immigration.
  B)  mutualism.
  C)  facilitation.
  D)  equilibrium.
  E)  inhibition.

50)  Based on the intermediate disturbance hypothesis, a community's species diversity is 50) ______
  A)  increased by stable conditions with no disturbance.
  B)  increased when humans intervene to eliminate disturbance.
  C)  increased by intensive disturbance by humans.
  D)  increased by moderate levels of disturbance.
  E)  increased by frequent massive disturbance.

51)  Which of the following is an example of cryptic coloration? 51) ______
  A)  bands on a coral snake
  B)  brown color of tree bark
  C)  a "walking stick" insect that resembles a twig
  D)  markings of a viceroy butterfly
  E)  colors of an insect-pollinated flower

52)  Approximately how many kg of carnivore production can be supported by a field plot containing 2000 kg of plant material? 52) ______
  A)  20,000
  B)  200
  C)  20
  D)  2,000
  E)  2

53)  Community ecologists would consider which of the following to be most significant in understanding the structure of an ecological community? 53) ______
  A)  determining how many species are present overall
  B)  the relative abundance of species
  C)  the kinds of interactions that occur among organisms of different species
  D)  which particular species are present
  E)  all of the above

Use the following diagram of a hypothetical food web to answer the following questions. The arrows represent the transfer of food energy between the various trophic levels.


Figure 54.2

54)  Which letter represents an organism that could be a producer? 54) ______
  A)  A
  B)  B
  C)  C
  D)  D
  E)  E

55)  Which of the following is the most accepted hypothesis as to why invasive species take over communities into which they have been introduced? 55) ______
  A)  Humans always select which species will outcompete the nuisance native species.
  B)  Invasive species have a higher reproductive potential than native species.
  C)  Invasive species are more aggressive than natives in competing for the limited resources of the environment.
  D)  Invasive species are not held in check by the predators and agents of disease that have always been in place for the natives.
  E)  Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive.

56)  Food chains are sometimes short because 56) ______
  A)  only a single species of herbivore feeds on each plant species.
  B)  most of the energy in a trophic level is lost as it passes to the next higher level.
  C)  predator species tend to be less diverse and less abundant than prey species.
  D)  local extinction of a species causes extinction of the other species in its food chain.
  E)  most producers are inedible.

57)  The principle of competitive exclusion states that 57) ______
  A)  two species cannot coexist in the same habitat.
  B)  two species that have exactly the same niche cannot coexist in a community.
  C)  two species will stop reproducing until one species leaves the habitat.
  D)  competition between two species always causes extinction or emigration of one species.
  E)  competition in a population promotes survival of the best-adapted individuals.

58)  The most plausible hypothesis to explain why species richness is higher in tropical than in temperate regions is that 58) ______
  A)  tropical regions generally have more available water and higher levels of solar radiation.
  B)  biodiversity increases as evapotranspiration decreases.
  C)  tropical regions have very high rates of immigration and very low rates of extinction.
  D)  tropical communities are younger.
  E)  higher temperatures cause more rapid speciation.

59)  Species richness increases 59) ______
  A)  as we increase in altitude in equatorial mountains.
  B)  as depth increases in aquatic communities.
  C)  as community size decreases.
  D)  on islands as distance from the mainland increases.
  E)  as we travel north from the South Pole.

Use the following diagram of a hypothetical food web to answer the following questions. The arrows represent the transfer of food energy between the various trophic levels.


Figure 54.2

60)  Which letter represents an organism that could be a carnivore? 60) ______
  A)  A
  B)  B
  C)  C
  D)  D
  E)  E

61)  A species of fish is found to require a certain water temperature, a particular oxygen content of the water, a particular depth, a rocky substrate on the bottom, and a variety of nutrients in the form of microscopic plants and animals to thrive. These requirements describe its 61) ______
  A)  resource partition.
  B)  home base.
  C)  ecological niche.
  D)  prime habitat.
  E)  dimensional profile.

62)  A community's actual evapotranspiration is a reflection of 62) ______
  A)  the depth of the water table.
  B)  energy availability.
  C)  solar radiation, temperature, and water availability.
  D)  the number of plants and how much moisture they lose.
  E)  plant biomass and plant water content.

63)  A population's carrying capacity 63) ______
  A)  can be accurately calculated using the logistic growth model.
  B)  increases as the per capita growth rate (r) decreases.
  C)  generally remains constant over time.
  D)  can never be exceeded.
  E)  may change as environmental conditions change.

64)  Density-dependent factors are related to which of the following? 64) ______
  A)  semelparous
  B)  cohort
  C)  Allee effect
  D)  iteroparous
  E)  dispersion

65)  Which of the following graphs refer to this equation?
=0.5 N
65) ______
  A) 
  B) 
  C) 
  D) 
  E) 

66)  Which of the following might be expected in the logistic model of population growth? 66) ______
  A)  As N approaches K, r increases.
  B)  As N approaches K, d increases.
  C)  Both A and B are true.
  D)  Both B and C are true.
  E)  As N approaches K, b increases.

67)  Population ecologists follow the fate of same-age cohorts to 67) ______
  A)  determine the factors that regulate the size of a population.
  B)  determine if a population's growth is cyclic.
  C)  determine if a population is regulated by density-dependent processes.
  D)  determine the birth rate and death rate of each group in a population.
  E)  determine a population's carrying capacity.

68)  Which of the following is the pattern of spacing for individuals within the boundaries of the population? 68) ______
  A)  semelparous
  B)  dispersion
  C)  iteroparous
  D)  Allee effect
  E)  cohort

69)  In models of sigmoidal (logistic) population growth, 69) ______
  A)  new individuals are added to the population most rapidly at the beginning of the population's growth.
  B)  carrying capacity is never reached.
  C)  population growth rate slows dramatically as N approaches K.
  D)  only density-independent factors affect the rate of population growth.
  E)  only density-dependent factors affect the rate of population growth.

70)  Logistic growth of a population is represented by dN/dt = 70) ______
  A)  rN
  B) 
  C)  rN
  D)  rN (K + N)
  E)  rN


Infant mortality and life expectancy at birth in developed and developing countries. (Data as of 2005.)
Figure 53.4

71)  What is a logical conclusion that can be drawn from the graphs above? 71) ______
  A)  Developed countries have higher infant mortality rates and lower life expectancy than developing countries.
  B)  Developed countries have lower infant mortality rates and lower life expectancy than developing countries.
  C)  Developed countries have higher infant mortality rates and higher life expectancy than developing countries.
  D)  Developed countries have lower infant mortality rates and higher life expectancy than developing countries.

72)  Life tables are most useful in determining which of the following? 72) ______
  A)  population dispersion patterns
  B)  carrying capacity
  C)  reproductive rates
  D)  the fate of a cohort of newborn organisms throughout their lives
  E)  immigration and emigration rates

73)  According to the logistic growth equation dN/dt = rmaxN(KN)/K, 73) ______
  A)  the per capita growth rate (r) increases as N approaches K.
  B)  population growth is zero when N equals K.
  C)  the number of individuals added per unit time is greatest when N is close to zero.
  D)  the population grows exponentially when K is small.
  E)  the birth rate (b) approaches zero as N approaches K.

74)  The observation that members of a population are uniformly distributed suggests that 74) ______
  A)  the density of the population is low.
  B)  resources are distributed unevenly.
  C)  the size of the area occupied by the population is increasing.
  D)  the members of the population are neither attracted to nor repelled by one another.
  E)  the members of the population are competing for access to a resource.

75)  Your friend comes to you with a problem. It seems his shrimp boats aren't catching nearly as much shrimp as they used to. He can't understand why because originally he caught all the shrimp he could handle. Each year he added a new boat, and for a long time each boat caught tons of shrimp. As he added more boats, there came a time when each boat caught somewhat fewer shrimp, and now, each boat is catching a lot less shrimp. Which of the following topics might help your friend understand the source of his problem? 75) ______
  A)  a K-selected population switching to an r-selected population
  B)  exponential growth curves and unlimited environmental resources
  C)  density-dependent population regulation and intrinsic characteristics of population growth
  D)  density-independent population regulation and chance occurrence
  E)  pollution effects of a natural environment and learned shrimp behavior

76)  Uniform spacing patterns in plants such as the creosote bush are most often associated with 76) ______
  A)  competitive interactions among individuals in the population.
  B)  patterns of high humidity.
  C)  chance.
  D)  the random distribution of seeds.
  E)  the concentration of nutrients within the population's range.

77)  Demography is the study of 77) ______
  A)  life expectancy of individuals within a population.
  B)  death and emigration rates of a population at any moment in time.
  C)  the vital statistics of populations and how they change over time.
  D)  reproductive rates of a population during a given year.
  E)  the survival patterns of a population.

78)  Which of the following statements about human population in industrialized countries is incorrect? 78) ______
  A)  Average family size is relatively small.
  B)  The population has undergone the demographic transition.
  C)  The survivorship curve is Type I.
  D)  Age distribution is relatively uniform.
  E)  Life history is r-selected.

79)  A population is correctly defined as having which of the following characteristics?
I. inhabiting the same general area
II. individuals belonging to the same species
III. possessing a constant and uniform density and dispersion
79) ______
  A)  I and II only
  B)  I, II, and III
  C)  I only
  D)  III only
  E)  II and III only

80)  Exponential growth of a population is represented by dN/dt = 80) ______
  A)  rN
  B)  rN
  C) 
  D)  rN (K + N)
  E)  rN

81)  Which of the following is a likely graphic outcome of a population of deer introduced to an island with an adequate herbivory and without natural predators, parasites, or disease? 81) ______
  A) 
  B) 
  C) 
  D) 
  E) 

82)  Which of the following statements best describes the difference in approach to studying the environment by early naturalists compared to present-day ecologists? 82) ______
  A)  Early naturalists manipulated the environment and observed changes in plant and animal populations, while modern ecology focuses on population dynamics.
  B)  Early naturalists systematically recorded what they observed in their environment; modern ecology is only concerned with man's impact on the environment.
  C)  Early naturalists employed a descriptive approach; present-day ecologists generate hypotheses, design experiments, and draw conclusions from their observations.
  D)  Early naturalists were interested in interactions between organisms and their environment; present day ecologists are interested in interactions between organisms.
  E)  Early naturalists were interested with man's interaction with the natural world; present-day ecologists seek to link ecology to developmental biology.

83)  Turnover of water in temperate lakes during the spring and fall is made possible by which of the following? 83) ______
  A)  cold, more dense water layered at the bottom
  B)  currents generated by nektonic animals
  C)  a distinct thermocline between less dense warm water and cold, dense water.
  D)  warm, less dense water layered at the top
  E)  the density of water changes as seasonal temperatures change.

84)  You are working for the Environmental Protection Agency and researching the effect of a potentially toxic chemical in drinking water. There is no documented scientific evidence showing that the chemical is toxic, but many suspect it to be a health hazard. Using the precautionary principle, what would be a reasonable environmental policy? 84) ______
  A)  Establish no regulations until there are conclusive scientific studies.
  B)  Set the acceptable levels of the chemical conservatively low, and keep them there unless future studies show that they can be safely raised.
  C)  Establish a contingency fund to handle insurance claims in the event that the chemical turns out to produce negative health effects.
  D)  Caution individuals to use their own judgment in deciding whether to drink water from a potentially contaminated area.
  E)  Set the acceptable levels at the highest levels encountered, and keep them there unless future studies demonstrate negative health effects.

85)  Which of the following statements about light in aquatic environments is correct? 85) ______
  A)  Longer wavelengths penetrate to greater depths.
  B)  Light penetration seldom limits the distribution of photosynthetic species.
  C)  Photosynthetic organisms that live in deep water probably use red light.
  D)  Most photosynthetic organisms avoid the surface where the light is not too intense.
  E)  Water selectively reflects and absorbs certain wavelengths of light.

86)  Where would an ecologist find the most phytoplankton in a lake? 86) ______
  A)  aphotic zone
  B)  benthic zone
  C)  profundal zone
  D)  photic zone
  E)  oligotrophic zone

87)  Which of the following statements about ecology is incorrect? 87) ______
  A)  Ecological studies may involve the use of models and computers.
  B)  Ecologists may study populations and communities of organisms.
  C)  Ecology is a discipline that is independent from natural selection and evolutionary history.
  D)  Ecology is the study of the interactions between biotic and abiotic aspects of the environment.
  E)  Ecology spans increasingly comprehensive levels of organization, from individuals to ecosystems.

88)  If Earth's axis of rotation suddenly became perpendicular to the plane of its orbit, the most predictable effect would be 88) ______
  A)  a big change in the length of the year.
  B)  no more night and day.
  C)  a cooling of the equator.
  D)  the elimination of ocean currents.
  E)  a loss of seasonal variation at high latitudes.

89)  Which of the following biomes is correctly paired with the description of its climate? 89) ______
  A)  temperate broadleaf forest-relatively short growing season, mild winters
  B)  savanna-low temperature, precipitation uniform during the year
  C)  tropical forests-nearly constant day length and temperature
  D)  tundra-long summers, mild winters
  E)  temperate grasslands-relatively warm winters, most rainfall in summer

90)  Which of the following organisms is the most likely candidate for geographic isolation? 90) ______
  A)  bat
  B)  squirrel
  C)  land snail
  D)  sparrow
  E)  salt-water fish

91)  Probably the most important factor(s) affecting the distribution of biomes is (are) 91) ______
  A)  species diversity.
  B)  proximity to large bodies of water
  C)  climate.
  D)  wind and ocean water current patterns.
  E)  day length and rainfall.

92)  Which of the following statements best describes the effect of climate on biome distribution? 92) ______
  A)  It is not only the average climate that is important in determining biome distribution, but also the pattern of climatic variation.
  B)  Correlation of climate with biome distribution is sufficient to determine the cause of biome patterns.
  C)  Temperate forests, coniferous forests, and grasslands all have the same mean annual temperatures and precipitation.
  D)  Fluctuation of environmental variables is not important if areas have the same annual temperature and precipitation means.
  E)  Knowledge of annual temperature and precipitation is sufficient to predict which biome will be found in an area.

93)  Of the following examples of ecological effect leading to an evolutionary effect (), which is most correct? 93) ______
  A)  A few organisms of a larger population survive a drought these survivors then emigrate to less arid environments.
  B)  A few individuals with denser fur survive the coldest days of an ice age the reproducing survivors all have long fur.
  C)  The insects that spend the most time exposed to sunlight have the most mutations.
  D)  Fish that swim the fastest in running water catch the most prey and more easily escape predation.
  E)  When seeds are not plentiful trees produce more seeds.

94)  In which of the following terrestrial biome pairs are both dependent upon periodic burning? 94) ______
  A)  grassland and tundra
  B)  tundra and coniferous forest
  C)  desert and savanna
  D)  tropical forest and temperate broadleaf forest
  E)  chaparral and savanna

95)  Generalized global air circulation and precipitation patterns are caused by 95) ______
  A)  Mountain ranges that deflect air masses containing variable amounts of moisture.
  B)  polar, cool, moist high pressure air masses from the poles that move along the surface, releasing precipitation along the way to the equator where they are heated and dried.
  C)  the revolution of the Earth around the sun.
  D)  air masses that are dried and heated over continental areas that rise, cool aloft, and descend over oceanic areas followed by a return flow of moist air from ocean to land delivering high amounts of precipitation to coastal areas.
  E)  rising, warm, moist air masses cool and release precipitation as they rise and then at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics.

96)  Generally speaking, deserts are located in places where air masses are usually 96) ______
  A)  tropical.
  B)  descending.
  C)  humid.
  D)  expanding.
  E)  rising.

97)  In which community would organisms most likely have adaptations enabling them to respond to different photoperiods? 97) ______
  A)  abyssal
  B)  tropical forest
  C)  coral reef
  D)  savanna
  E)  temperate forest

98)  Which statement best contrasts environmentalism with ecology? 98) ______
  A)  Ecologists study organisms in environments that have been undisturbed by human activities; environmentalists study the effects of human activities on organisms.
  B)  Environmentalists are only involved in politics and advocating for protecting nature; ecologists are only involved in scientific investigations of the environment.
  C)  Ecology provides scientific understanding of living things and their environment; environmentalism is more about conservation and preservation of life on Earth.
  D)  Environmentalism is devoted to applied ecological science; ecology is concerned with basic/theoretical ecological science.
  E)  Ecology is the study of the environment; environmentalism is the study of ecology.

99)  As climate changes because of global warming, species' ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that 99) ______
  A)  produce well-provisioned seeds.
  B)  have thin seed coats.
  C)  disperse many seeds in close proximity to the parent tree.
  D)  have seeds that become viable only after a forest fire.
  E)  have seeds that are easily dispersed by wind or animals.

100)  Trees are not usually found in the tundra biome because of 100) ______
  A)  permafrost.
  B)  acidic soils.
  C)  overbrowsing by musk ox and caribou.
  D)  insufficient annual precipitation.
  E)  extreme winter temperatures.