Geosystems: An Introduction to Physical Geography, 9e (Christopherson)
Chapter 19 Ecosystem Essentials
19.1 Multiple Choice Questions
1) A self-regulating association of living plants and animals and their nonliving physical
environment is termed a(n)
A) ecosystem.
B) ecotone.
C) community.
D) niche.
2) An ecosystem is a(n) ________ system in terms of energy, and a(n) ________ system in terms
of matter.
A) open; open
B) open; closed
C) closed; open
D) closed; closed
3) The study of the interrelationships between organisms and their environment is called
A) biology.
B) ecology.
C) pedology.
D) biogeography.
4) The study of the distribution of plants and animals, the diverse spatial patterns they create, and
the physical and biological processes that produce Earth’s species richness is called
A) biology.
B) ecology.
C) geoarchaeology.
D) biogeography.
5) A study of the dietary requirements of African bush elephants (Loxodonta africana) in a
savanna environment, and the role the elephants play in that environment, would be an example
of a topic studied in
A) biogeography.
B) ecology.
C) pedology.
D) plant biology.
6) A study of the spatial distribution of the coast redwood (Sequoia sempervirens) and the
environmental factors that control that distribution would be an example of a topic studied in
A) biogeography.
B) ecology.
C) pedology.
D) plant biology.
7) The Earth’s biosphere
A) consists of only terrestrial organisms, while the hydrosphere includes aquatic and marine
organisms.
B) only includes the biotic components of an ecosystem, with the abiotic components being
considered part of the lithosphere, hydrosphere, or atmosphere, respectively.
C) is more a theoretical construct than an observable sphere of study.
D) extends from the ocean floor to an altitude of approximately 8 km (5 mi) into the atmosphere.
8) Which of the following is not a biotic component of an ecosystem?
A) plants
B) animals
C) bacteria
D) mineral nutrients
9) Which of the following is not a abiotic component of an ecosystem?
A) plants
B) sunlight
C) precipitation
D) mineral nutrients
10) Autotrophs that dwell in dark caves, in wells, or on the ocean floor often depend on which of
the following biogeochemical processes?
A) chemosynthesis
B) photosynthesis
C) nutrient leaching
D) nitrogen fixing
11) Of the total energy intercepted at Earth’s surface and available for work, only about
________ is actually fixed by photosynthesis.
A) 1%
B) 5%
C) 10%
D) 15%
12) An organism capable of synthesizing its own food and inorganic substances using sunlight or
chemical energy is known as a(n)
A) heterotroph.
B) autotroph.
C) primary consumer.
D) secondary consumer.
13) The gaseous oxygen in the Earth’s atmosphere was produced as a by-product of
A) volcanic outgassing.
B) photochemical reactions breaking down ozone (O3) to form oxygen (O2).
C) photosynthesis.
D) decay of organic matter.
14) Today, there are over 270,000 plant species with conductive tissues and material flow
systems known as
A) blue-green algae.
B) cyanobacteria.
C) xeriphytes.
D) vascular plants.
15) The openings on the surfaces of plant leaves through which gases move into and out of are
known as
A) chlorophyll.
B) stomata.
C) guard cells.
D) chloroplasts.
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16) Photosynthesis involves
A) the release of stored carbon dioxide in a process using sunlight.
B) the union of carbon dioxide and hydrogen in the presence of sunlight, and the release of
oxygen.
C) a process known as respiration.
D) important reactions within the stems and roots of plants.
17) 6CO2 + 6H2O + Light g C6H12O6 + 6O2
is the generalized equation for
A) respiration.
B) photosynthesis.
C) chemosynthesis.
D) transpiration.
18) C6H12O6 + 6O2
g 6CO2 + 6H2O + heat energy is the generalized equation for
A) respiration.
B) photosynthesis.
C) chemosynthesis.
D) transpiration.
19) Chlorophyll absorbs only the ________ and ________ wavelengths for photochemical
operations.
A) orange-red; violet-blue
B) violet-blue; green-yellow
C) orange-red; green-yellow
D) yellow-red; violet-green
20) Chlorophyll reflects predominately ________ wavelengths of visible light.
A) red
B) blue
C) green
D) indigo
21) Approximately ________ of the light energy arriving at the surface of a leaf is useful to
chlorophyll.
A) 5%
B) 10%
C) 25%
D) 50%
22) Photosynthesis converts
A) heat energy, carbon dioxide, and water into carbohydrates and oxygen.
B) heat energy, oxygen, and carbohydrates into carbon dioxide and water.
C) light energy, carbon dioxide, and water into carbohydrates and oxygen.
D) light energy, oxygen, and carbohydrates into carbon dioxide and water.
23) Respiration involves
A) the use of heat energy to react carbon dioxide with water to produce oxygen.
B) a chemical reaction between carbohydrates and oxygen to produce carbon dioxide, water, and
heat energy.
C) a photochemical reaction involving carbon dioxide and water to produce carbohydrates and
oxygen.
D) a photochemical reaction involving carbon dioxide and oxygen to produce water and oxygen.
24) The difference between the photosynthetic production of carbohydrates and the respiration
loss of carbohydrates is known as
A) net primary productivity.
B) compensation point.
C) net photosynthesis.
D) free air CO2 enrichment.
25) The net photosynthesis for an entire ecosystem is known as the
A) net primary productivity.
B) compensation point.
C) net photosynthesis.
D) free air CO2 enrichment.
26) The break-even point between the production and consumption of organic material is termed
A) net primary productivity.
B) compensation point.
C) net photosynthesis.
D) free air CO2 enrichment.
27) The net dry weight of all organic material in an ecosystem is known as
A) net primary productivity.
B) biomass.
C) net photosynthesis.
D) compensation point.
28)
In which of the following areas would one tend to find the highest net primary productivity?
A) northern Brazil
B) central Australia
C) western Canada
D) Euroasia
29) In which of the following terrestrial ecosystems would one tend to find the highest net
primary productivity?
A) temperate grassland
B) boreal forest
C) tropical seasonal forest
D) tundra and alpine region
30) In which of the following terrestrial ecosystems would one tend to find the lowest net
primary productivity?
A) extreme desert
B) woodland and shrubland
C) tundra
D) cultivated lands
31) In which of the following marine/aquatic ecosystems would one tend to find the highest net
primary productivity?
A) open ocean
B) boreal forest
C) algal beds and reefs
D) upwelling zone
32) Which of the following is incorrect regarding the spatial variability of net primary
productivity?
A) At temperate and high latitudes, the rate of carbon fixing is seasonally variable.
B) Productivity rates are constantly high throughout the year in the tropics.
C) Net primary productivity is highest in the fall and winter in temperate and high latitude areas.
D) Productivity rates in deserts is much less than that of tropical regions.
33) Together, three natural elements make up 99% of the Earth’s biomass. Which of the
following is not one of those three elements?
A) oxygen (O)
B) hydrogen (H)
C) nitrogen (N)
D) carbon (C)
34) Which of the following is the largest carbon sinks?
A) the atmosphere
B) fossil fuels and oil shales
C) dead organic matter
D) the oceans
35) How is atmospheric nitrogen converted to a usable form in the biosphere?
A) Atmospheric nitrogen is directly available to plants and animals.
B) It is absorbed into plants via stomata and converted within the plant to a usable form.
C) Bacteria within root nodules of legumes chemically combine the atmospheric nitrogen into
nitrates and ammonia.
D) Atmospheric nitrogen is completely unavailable to plants and animals and, as a result,
synthetic fertilizers must be used.
36) Which of the following is not correct regarding nitrogen.
A) The atmosphere contains about 78% nitrogen.
B) Bacterial action is key to the nitrogen cycle.
C) Atmospheric nitrogen is accessible directly to most organisms.
D) Nitrogen is very important to organisms.
37) A dead zone refers to
A) terrestrial areas in which excessive nitrogen fertilizer has essentially burned the soil,
preventing plants and microorganisms from living there.
B) oligotrophic areas in water bodies that cannot support life due to lack of nutrients.
C) an ecosystem that was cleared of all vegetation for slash and burn agriculture.
D) hypoxic areas in water bodies that limit marine and aquatic life.
38) Energy flows through an ecosystem along an idealized unidirectional pathway called a
A) food web.
B) niche order.
C) trophic cascade.
D) food chain.
39) Organisms that share the same feeding level (e.g. primary producers, primary consumers,
secondary consumers, etc.) are said to be at the same
A) food web.
B) niche order.
C) trophic level.
D) food pyramid.
40) A ________ is a complex network of interconnected food chains with multidirectional
branches.
A) food web
B) niche order
C) trophic level
D) food pyramid
41) Consider a simple food chain in which a grasshopper eats grass, the grasshopper is eaten by a
frog, and the frog is eaten by a snake. Which of the following is not correctly matched
A) grass — autotroph
B) grasshopper — herbivore
C) frog — secondary consumer
D) snake — primary consumer
42) A consumer, such as a bear, that eats both producers (plants) and consumers (animals) is a
A) herbivore.
B) carnivore.
C) omnivore.
D) detritivore.
43) Only about ________ of the kilocalories in a trophic level is passed to the next trophic level
(e.g. from autotroph to primary consumer).
A) 5%
B) 10%
C) 15%
D) 20%
44) From the perspective of energy, which of the following is the most efficient trophic level?
A) primary producer
B) primary consumer
C) secondary consumer
D) tertiary consumer
45) Currently, approximately ________ of cultivated acreage in the United States and Canada is
planted for animal consumption
A) 15%
B) 30%
C) 50%
D) 65%
46) As chemical pesticides move through the trophic pyramid, they may be amplified at each
higher level in a process called
A) biomagnification.
B) trophic cascading.
C) competitive exclusion.
D) pyramidal decay.
47) In food webs, toxic chemicals tend to accumulate and concentrate most in the
A) top carnivores.
B) herbivores.
C) omnivores.
D) autotrophs.
48) The interacting populations of living plants and animals in a particular location are described
as a(n)
A) metapopulation.
B) ecosystem.
C) community.
D) niche.
49) The environment in which an organism resides or is biologically adapted to live is called a(n)
A) ecotone.
B) habitat.
C) community.
D) niche.
50) The specific, unique role that a species performs within a given area is known as a(n)
A) ecotone.
B) habitat.
C) community.
D) niche.
51) The proposition that no two species can occupy the same ecological niche is known as the
A) symbiosis.
B) competitive exclusion principle.
C) trophic pyramid theory.
D) ecological niche theory.
52) Lichen are made up of algae and fungi living together. In this relationship, the alga is the
produce and for source for the fungus and the fungus provides structure and physical support for
the alga. This is an example of which symbiotic relationship?
A) parasitism
B) mutualism
C) commensalism
D) amensalism
53) In coral reefs, clownfish live unharmed among the poisonous tentacles of sea anemones. The
sea anemones protect the clownfish from predation, while the clownfish scare off predators, such
butterfly fish, which would otherwise eat the anemones. The clownfish may also provide
important nutrients to the anemones. This is an example of which symbiotic relationship?
A) parasitism
B) mutualism
C) commensalism
D) amensalism
54) Mistletoe (Phoradendron) infest many taxa of plants, often causing the branches of the host
species to become swollen and distorted and making the trees more susceptible to insect
infestations. This is an example of which symbiotic relationship?
A) parasitism
B) mutualism
C) commensalism
D) amensalism
55) Epiphytic plants, such as various species of orchids (Orchidaceae), grow upon another plant,
using the plants for physical support, but bringing no harm to the host plant. This is an example
of which symbiotic relationship?
A) parasitism
B) mutualism
C) commensalism
D) amensalism
56) A black walnut (Juglans nigra) emits a chemical that may kill or inhibit the growth of other
nearby shrubs or trees. However, the black walnut is unaffected by this interaction. This is an
example of which symbiotic relationship?
A) parasitism
B) mutualism
C) commensalism
D) amensalism
57) The zonation of flora and fauna along an altitudinal transect similar to that found along
latitudinal transects is known as the
A) altitude-latitude hypothesis.
B) vegetation similarity theory.
C) the life zone concept.
D) altitudinal zonation principle.
58) ________ refers to the biotic and abiotic characteristics in the environment that determine
species distribution.
A) Limiting factor
B) Range of tolerance
C) Ecological niche
D) Habitat