Reference no: EM1389997

5. Assume that lions running on grass neither benefit nor are harmed by this interaction, but their activity helps the grass grow. This is an example of a
a. mutualism.
b. endosymbiosis.
c. commensalism.
d. symbiosis.
e. ammensalism.
6. In addition to positive interactions, the collective term for mutualisms and commensalisms is
a. amelioration.
b. conciliation.
c. facilitation.
d. benefactory.
e. symbiosis.
7. Mycorrhizae are generally mutualistic associations between a higher plant and a fungus. Under which of the following environmental conditions might this mutualism change into a form of parasitism by the fungus on the plant?
a. High light
b. Low light
c. Low nutrient availability in soil
d. B and C
e. None of the above
8. Which of the following statements about mutualisms is true?
a. Mutualisms usually impose costs on the partners.
b. Partners do not join mutualisms for altruistic reasons.
c. Conflicts of interest seldom exist in mutualisms.
d. Both a and b
e. Both a and c
9. Which of the following statements about the difference between a competitive network and a competitive hierarchy is true?
a. A competitive network comprises more species.
b. The interactions are stronger in a competitive network than in a competitive hierarchy.
c. In a competitive hierarchy, one species dominates the interaction; in a competitive network, no one species dominates.
d. Both a and b
e. None of the above
10. Mushroom-feeding Drosophila species, including the species Drosophila neotestacea, D. falleni, D. putrida, and D. recens, are prevalent in the Great Lakes region of the United States. Suppose a biologist collects flies from three different communities and obtains results shown in the table below.
Community 1
Species Abundance Proportion (pi) ln (pi) pi ln (pi)
D. neotestacea 24 0.48 -0.734 -0.352
D. falleni 16 0.32 -1.139 -0.365
D. putrida 6 0.12 -2.120 -0.254
D. recens 4 0.08 -2.526 -0.220
Total 50 1.00
Community 2
Species Abundance Proportion (pi) ln (pi) pi ln (pi)
D. neotestacea 38 0.38 -0.968 -0.368
D. falleni 32 0.32 -1.139 -0.365
D. putrida 30 0.30 -2.204 -0.361
Total 100 1.00
Community 3
Species Abundance Proportion (pi) ln (pi) pi ln (pi)
D. neotestacea 44 0.44 -0.821 -0.361
D. falleni 37 0.37 -1.994 -0.368
D. putrida 19 0.19 -1.661 -0.316
Total 100 1.00
Rank the species diversity based on the Shannon index from highest to lowest.
a. Community 1 > Community 2 > Community 3
b. Community 1 > Community 3 > Community 2
c. Community 2 > Community 1 > Community 3
d. Community 2 > Community 3 > Community 1
e. Community 3 > Community 2 > Community 1
Refer to the diagram below for questions 11-12
11. Where would a keystone species most likely be located in the diagram?
a. Position A
b. Position B
c. Position C
d. Position D
e. Position E
12. Where would a foundation species most likely be located in the diagram?
a. Position A
b. Position B
c. Position C
d. Position D
e. Position E
13. Which of the following early ecologists maintained that plant communities were analogous to "superorganisms"?
a. Henry Cowles
b. Fredrick Clements
c. Henry Gleason
d. F. Stuart Chapin
e. John Sutherland
14. The big circle at the upper left of the figure below represents
a. primary succession.
b. secondary succession.
c. patch dynamics.
d. a situation in which communities cannot persist.
e. no succession.
15. At which stage of succession is facilitation usually most important?
a. Early
b. Middle
c. Late
d. Facilitation is equally important in middle and late stages.
e. At no stage is facilitation important.
16. The final theoretical stage of succession is called the _______ stage.
a. omega
b. ultimate
c. penultimate
d. climax
e. pioneer
17. Which of the following cannot be a factor determining the composition of communities?
a. Regional species pools
b. Dispersal ability of species
c. Abiotic conditions
d. The nature of interactions between introduced species and species already in the community
e. All of the above can be factors determining species composition.
18. A weed that is ordinarily invasive is unable to become established in a meadow community because the roots of other plant species produce chemicals that retard the weed's growth. This is an example of
a. resource partitioning.
b. biotic resistance.
c. bdelloidism.
d. competitive displacement.
e. resilience.
19. Which of the following is an assumption of the resource partitioning theory?
a. Species differ in their intrinsic population growth rates.
b. Resources are limiting.
c. Populations have reached stable population sizes.
d. Both a and b
e. Both b and c
20. What was Hutchinson's solution to the "paradox of the plankton"?
a. Predation checked the superior competitor.
b. The coexisting species used different ratios of limiting resources.
c. Seasonal changes prevented any one species from competitively excluding the others.
d. Migration from other lakes maintained species diversity.
e. Natural selection enabled species to thwart competitive exclusion.
21. Chemical energy derived from the fixation of carbon by photosynthesis and chemosynthesis is known as _______ production.
a. net
b. gross
c. secondary
d. primary
e. carbon
22. Which of the following correctly represents the relationship between net primary production (NPP) and gross primary production (GPP)?
a. NPP + biosynthesis = GPP
b. NPP = GPP + chemosynthesis
c. NPP + chemosynthesis = GPP
d. NPP = GPP + respiration
e. NPP = GPP - respiration
23. Harvest techniques would likely be most problematical when estimating NPP in ________ because _______.
a. temperate grasslands; the growth rate is very rapid
b. temperate grasslands; tissues that die decompose rapidly
c. tropical rainforests; the growth rate is very rapid
d. tropical rainforests; tissues that die decompose rapidly
e. temperate forests; the growth rate is very rapid
24. Which of the following statements about net secondary production is false?
a. In most ecosystems, net secondary production is only a small fraction of NPP.
b. As a percentage of NPP, net secondary production is usually lower in terrestrial ecosystems than in aquatic ecosystems.
c. In most terrestrial ecosystems, the highest percentage of net secondary production is associated with detritivores.
d. Net secondary production depends on the digestibility and nutrient content of the heterotrophs' food.
e. All of the above are true; none are false.
25. Which trophic level generates the most dead organic material in most ecosystems?
a. The first
b. The second
c. The third
d. The fourth
e. All trophic levels generate about the same amount of organic material.
26. Which of the following statements about NPP and consumption by heterotrophs is true?
a. Consumption correlates positively with NPP in both aquatic and terrestrial ecosystems.
b. Consumption correlates positively with NPP in aquatic ecosystems, but it shows no significant relationship to NPP in terrestrial ecosystems.
c. Consumption correlates positively with NPP in terrestrial ecosystems, but it shows no significant relationship to NPP in aquatic ecosystems.
d. Consumption correlates positively with NPP in aquatic ecosystems and negatively with NPP in terrestrial ecosystems.
e. Consumption shows no significant relationship to NPP in either aquatic or terrestrial ecosystems.
27. Compared to carnivores, herbivores tend to have _______ assimilation energies because _______.
a. lower; they are smaller in size
b. lower; plants contain many substances such as cellulose that are not easily digested.
c. higher; they are larger in size.
d. higher; plants and animals have different C:N ratios.
e. higher; plants contain many substances such as cellulose that are not easily digested.
28. In bottom-up control, energy flow through the ecosystem is determined primarily by the
a. supply of resources limiting NPP.
b. production efficiencies of herbivores.
c. assimilation efficiencies of herbivores.
d. abundance of detritivores.
e. abundance of carnivores.
29. A group of individuals of a single species living in a particular area and interacting with one another is called a(n)
a. biosphere.
b. community.
c. ecosystem.
d. population.
e. None of the above
30. Which of the following terms refers to a community of organisms plus the physical environment in which they live?
a. Biosphere
b. Community
c. Ecosystem
d. Population
e. None of the above
31. Mediterranean climates are typically found on the _______ coast of a continent at about _______ North or South of the equator.
a. east; 25°
b. east; 35°
c. east; 50°
d. west; 35°
e. west; 50°
32. Compared with land at the same latitude, ocean waters tend to be _______ in the winter and _______ in the summer because water has a _______ heat capacity than land has.
a. warmer; warmer; higher
b. warmer; warmer; lower
c. warmer; colder; higher
d. colder; warmer; higher
e. colder; colder; lower
33. Which of the following statements about tropical seasonal forests and savannas is true?
a. Their seasonality is due largely to movements of the Intertropical Convergence Zone.
b. Despite human activity, more than 80% of this biome remains intact.
c. Deciduousness is very rare in this biome.
d. Both a and b
e. Both b and c
34. Based on the climate data shown in the graph, the location most likely charted here is in the _______ biome.
a. tropical seasonal forest
b. temperate evergreen forest
c. boreal forest
d. temperate deciduous forest
e. temperate shrubland and woodland
35. Which of the following factors determines the potential geographic range of a species?
a. Its ability to tolerate extreme environmental conditions of the range
b. Its ability to migrate away from the range
c. Its ability to acquire energy and resources from the range
d. Both a and b
e. Both a and c
36. Leaves that are comparatively _______ and _______ lose the most heat to wind because they have _______layers than other leaves.
a. small; smooth; thinner boundary
b. small; smooth; thicker convection
c. small; smooth; thinner convection
d. large; rough; thinner convection
e. large; rough; thinner boundary
37. Chlorophyll absorbs _______ light and reflects green wavelengths.
a. blue
b. green
c. red
d. blue and green
e. blue and red
38. Curves A and B of the graph below represent the reflectance rates of solar and infrared radiation of two different leaves of the warm desert species Encelia farinosa. According to the graph, curve A represents _______, while curve B represents _______.
a. a leaf from a plant grown in a moist environment; a leaf from a plant grown in a dry
environment
b. a summer leaf; a winter leaf
c. a winter leaf; a summer leaf
d. a leaf with comparatively more stomates; a leaf with fewer stomates
e. a leaf with a boundary layer; a leaf without a boundary layer
39. Suppose a population of shorthorn cattle has only two alleles (R and r) at a locus. If the frequency of Ris 0.37, what is the frequency of r?
a. 0.37
b. 0.5
c. 0.63
d. 0.77
e. The frequency of r cannot be computed based on the information above.
40. Which of the following processes changes allele frequencies by chance alone?
a. Disruptive selection
b. Genetic drift
c. Gene flow
d. Both a and b
e. Both b and c
41. An organism's life history involves
a. growth.
b. development.
c. survival.
d. All of the above
e. None of the above
42. In many species of salamanders, eggs hatch into juveniles that look like miniature adults. Biologists call this type of life history
a. alternation of generations.
b. direct development.
c. gametophytic development.
d. diapause.
e. None of the above
43. There are 80 swamp sparrows in a 20-hectare section of Mount Meadow. The average population density of sparrows at this site is _______ per hectare.
a. 2
b. 4
c. 20
d. 80
e. 160
44. Which of the following terms refers to the physiologically independent plants?
a. Biotic
b. Gamete
c. Ramet
d. Genet
e. Quadrat
45. Evergreen foliage would most likely be found in which of Grime's categories of plants?
a. Competitive
b. Ruderal
c. Ontogenetic
d. Stress-tolerant
e. Polyphenism
46. Which of the following statements about a population that is growing and has reached and maintains a stable age distribution is false?
a. Its ? will be relatively constant.
b. The age structure of the population will not change from one year to the next.
c. Its growth rate will be relatively constant.
d. The number of individuals in each age class will increase by a constant multiplier every year.
e. All of the above are true.
47. Which of the following statements about logistic growth is false?
a. The standard logistic equation assumes that the carrying capacity is a constant.
b. Changes in environmental conditions can cause the carrying capacity to fluctuate.
c. The term "logistic growth" is used broadly to indicate any population whose numbers rise initially but then level off at a maximum population size.
d. Variation in the birth rate that occurs at a particular density can lead to variation in the carrying capacity.
e. All of the above are true.
48. Assuming that their average population growth rates and all other factors are equal, which of the following populations would most likely be at risk for extinction?
a. A large population with low variation in its growth rate
b. A large population with high variation in its growth rate
c. A small population with low variation in its growth rate
d. A small population with high variation in its growth rate
e. All have equal risk; population size and variation in growth rate do not influence extinction risk.
49. Soil salinity affects the growth rate of plants but is not depleted by the plants. Which of the following terms best describes salinity in this situation?
a. Allelopathic agent
b. Resource
c. Isocline
d. Gausian factor
e. Physical factor
50. Black walnut trees release juglone and other chemicals that can be toxic to other plants. This is a possible example of
a. isoclines.
b. exploitation competition.
c. allelopathy.
d. character displacement.
e. chthamalus.
51. Which of the following is not an exploitative relationship?
a. Parasitism
b. Parasitoidism
c. Predation
d. Herbivory
e. All of the above are exploitative relationships.
52. Herbivores most commonly eat the _______ of plants.
a. seeds
b. stems
c. roots
d. leaves
e. Both a and b