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FINAL EXAM ECOLOGY 100
DR. ISOBEL A. PEARSALL
NAME____________________
Multiple choice questions. (1 mark each)
1. Changes in community structure over time are called _____________.
a. succession
b. stratification
c. zonation
d. characterization
2. Food webs can be arranged into ________ levels based on whether organisms
obtain their nutrition from photosynthesis, from eating plants, or from eating
animals
a. niche
b. guild
c. trophic
d. predation
3. A dominant species in a community may
a. Be the most numerous
b. Possess the highest biomass
c. Preempt the most space
d. Make the largest contribution to energy flow or nutrient cycling
e. All of the above
4. Which of the following does NOT function as a habitat corridor?__________
a. a large lake
b. a hedgerow
c. the vegetation along a river
d. a drainage ditch
5. Which of the following is produced by humans as pesticides, soluble in fats and
lipids, and accumulates in animals through the food chain?________
a. lead
b. chlorinated hydrocarbons
c. sulfur dioxide
d. carbon dioxide
6. In the small-population approach to studying endangered populations, the key
factor driving the species towards extinction is___________
a. loss of genetic variation
b. too many animals migrating away from small populations
c. loss of food
d. increased risk of predation
e. too many animals migrating between populations
7. Which of the following is NOT true?_________
a. the world’s oceans act as a sink for carbon dioxide
b. the world’s terrestrial ecosystems act as a sink for carbon dioxide
c. the world’s ecosystems act as sinks for carbon dioxide, completely
offsetting the increase in carbon dioxide emissions from burning of fossil
fuels.
d. Reforestation is part of the solution to balancing the global carbon cycle.
8. Which of the following allocates more biomass to photosynthetic tissue and less
to supportive tissue?
a. Trees
b. Shrubs
c. Lianas
d. Grasses
9. Conservationists refer to the number of individuals necessary to ensure the longterm survival of a species as the _____________
a. Minimum viable population
b. Genetically effective population
c. metapopulation
d. carrying capacity
10. Which terrestrial biome has the highest diversity of plant and animal life?
a. Tropical savanna
b. Tropical rain forest
c. Temperate deciduous forest
d. Boreal forest
11. An endemic species is best defined as a species that___________________
a. is a habitat specialist with a large geographic distribution
b. has so few individuals remaining that is ceases to perform its role within
an ecosystem
c. no longer exists in a given area yet still survives elsewhere
d. occurs in a single geographic area and nowhere else
12. The primary cause of current extinction is____________________
a. overhunting
b. introduction of non-native species
c. pollution
d. habitat degradation
13. Harvesting at a level that will ensure a similar yield repeatedly without forcing the
population into decline is called_____________________
a. crop skimming
b. enduring harvest
c. sustained yield
d. consistent crop
14. The rate of carbon cycling is determined by the rate of _______________
a. mineral weathering
b. primary production
c. decomposition
d. none of the above
e. both B and C
15. The General Circulation Models developed by atmospheric scientists predict that
in the future
a. Temperatures, sea levels, variability of climate and precipitation will all
increase
b. Temperatures, sea levels, and variability of climate will increase while
precipitation will decrease
c. Temperatures and sea levels will increase, while variability of climate and
precipitation will both decrease
d. Temperatures and precipitation will increase while sea levels and
variability of climate will decrease
16. Higher trophic levels in a food chain contain ___________ energy compared to
lower trophic levels
a. less
b. more
c. equal
d. more variable
17. The area of suitable habitat necessary for maintaining the number of individuals
and ensuring the long-term survival of a species should be highest for a
_________________
a. small herbivore
b. large herbivore
c. small carnivore
d. large carnivore
18. The innate rhythm of activity of organisms covering approximately a 24-hour
period is called _______.
a. photoperiod
b. ritualization
c. circadian rhythm
d. synchronization
19. Which statement about stress is incorrect? _________
a. As population density increases stress increases mutations
b. Stress triggers changes in the endocrine system of animals
c. Stress can stimulate growth and increase the rate of reproduction
d. Stress may result in profound changes in the immune system.
20. The maximum number of individuals a habitat can support is called
the__________
a. reproductive potential
b. carrying capacity
c. community size
d. density-dependent factor
e. population growth
Short answer questions. (1 mark each). Write the word or phrase that best
completes the statement or answers the question.
1. The smaller an organism, the ____________ its surface-to-volume ratio.
2. The number of species in a community is called __________________________.
3. The ______________________________ principle says that two complete
competitors cannot exist.
4. __________________________ is the complete removal of a forest during
harvest.
5. Predation, in which the predator and prey are the same species is called
_____________.
6. A functional response in which the number of prey taken per predator increases
quickly at first with prey density, and then increases at a much slower rate as prey
density continues to increase, is called a Type _____________.
7. Plants that grow where we do not want them to grow are called
________________.
8. Strips of habitat that connect habitat patches are referred to as ______________.
9. Succession that occurs on a site which was previously not occupied by a
community is called _____________ succession
10. The rate of nutrient cycling in an ecosystem depends on the rates of two key
processes, primary productivity and _____________________
11. The portion of the fundamental niche that an organism actually exploits in the
presence of competitors is called its ___________________ niche.
12. The relationship between the per capita rate of consumption and the number of
prey is known as the predator’s _____________________.
13. A(n) ______________ is an intermediate organism that aids the spread of a
parasite from one host to another.
14. A relationship between two species, where one species benefits and the other is
not significantly affected is called ________________.
15. ______________ primary production is the total rate of photosynthesis, or energy
assimilated by plants.
True/False questions. Write T is the statement is true, and F is the statement is false.
(1 mark each).
1. An ecosystem contains both living and non-living components.________
2. The basic Lotka-Volterra models of predator-prey interactions predict that
predators will drive the prey extinct._____________
3. A parasite usually kills its host.______________
4. In Batesian mimicry, one poisonous prey species has evolved the same warning
colouration as another poisonous prey species._______________
5. As patch size increases, the ratio of interior to edge increases._______________
6. When two of more organisms use a portion of the same resource simultaneously,
it is referred to as niche overlap.__________
7. The biogeochemical cycles of one ecosystem are typically independent of those of
other ecosystems.______
8. There are generally few species at higher altitudes than at lower
altitudes.________
9. A Type I functional response leads to regulation of the prey population by the
predator. _____________
10. The phosphorus cycle has essentially no atmospheric content. ________________
11. The competitive ability of an organism remains constant even when
environmental conditions change. ___________________
12. In the early stages of plant succession, shade-intolerant species are often common.
_________________
Please answer the following questions:
1. Use examples to illustrate the difference between a dominant species and a
keystone species (4 marks)
2. Explain how restoration ecology, including bioremediation and biological
augmentation, helps return degraded ecosystems to near-natural pre-degraded
states. Describe examples of both approaches (6 marks).
Long answer questions
Please answer 2 of the following questions (5 marks each)
1. Describe three components of biodiversity. Explain how human activities are a
threat to biodiversity. Distinguish between threatened species and endangered
species.
2. What is global warming? Describe the causes and consequences of global
warming.
3. List the main predictions of the theory of island biogeography, and explain the
reasons for those predictions.
4. Describe why most plants have a variety of chemicals, spines and thorns for
defense against herbivores. Define coevolution and describe two examples.
5.
Explain the difference between the two basic types of biogeochemical cycles,
using specific examples of each.
6.
What is the difference between deciduous and evergreen trees? List the two main
types of deciduous and the two main types of evergreen leaves and where they are
found. Why are they found associated with these environments?
7. Explain how it is possible for a diversity of potential competitors to coexist in the
same community, despite the competitive exclusion principle.