Deck 55: Ecosystems and the Biosphere

Question 1

Which statement reflects a key concept about ecosystems?

A) Matter moves linearly through different systems, both abiotic and biotic, within an ecosystem.
B) There is a one-way flow of energy through the food webs of ecosystems.
C) Conservation should focus on the success and survival of individual species.
D) The abiotic environment does not influence the distribution and survival of particular organisms.
E) Heat energy can be used by organisms for their daily activities.

Answer 1

B

Question 2

Figure 55-1 ​

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The accompanying figure represents a

A) fairly simple food web.
B) fairly simple food chain.
C) pyramid of biomass.
D) pyramid of energy.
E) pyramid of numbers.

Answer 2

C

Question 3

Figure 55-2 ​

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The accompanying figure is a good illustration of

A) bioconcentration.
B) biological magnification.
C) persistence.
D) narrow-spectrum botanicals.
E) the pesticide treadmill.

Answer 3

B

Question 4

Net primary productivity represents

A) the rate at which energy is captured during photosynthesis.
B) the amount of biomass in excess of that needed to support plant cell respiration.
C) the amount of carbon dioxide produced by plants.
D) plant reproduction per unit area per unit time.
E) energy production in an area per unit time.

Question 5

In an ecosystem, which measure of energy is the largest in amount or rate?

A) Net primary productivity
B) Gross primary productivity
C) Plant respiration
D) Animal respiration
E) Both plant and animal respiration

Question 6

Figure 55-2 ​

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In the accompanying figure, the gull has the highest concentration of DDT because it is

A) a more complex organism.
B) an older organism.
C) at the bottom of the food chain.
D) at the top of the food chain.
E) homoeothermic (warm-blooded).

Question 7

Organisms that eat plants exclusively are known as______.

A) secondary consumers
B) autotrophs
C) omnivores
D) heterotrophs
E) herbivores

Question 8

Which statement best describes a typical food chain?

A) An owl has a positive impact on the grass population.
B) An owl has a negative impact on the grass population.
C) A carnivore has a negative effect on primary producers.
D) Energy can flow back and forth between trophic levels.
E) Energy is never lost as it moves from one trophic level to the next.

Question 9

Which pair best represents photosynthetic organisms?

A) Primary producer and autotroph
B) Primary consumer and autotroph
C) Primary producer and heterotroph
D) Primary consumer and heterotroph
E) Primary producer and saprotroph

Question 10

A linear depiction of energy flow in an ecosystem is a(n)

A) food web.
B) food chain.
C) trophic web.
D) ecological pyramid.
E) pyramid of numbers.

Question 11

What key factor limits the number of trophic levels in an ecosystem?

A) Maximum solar radiation
B) Energy loss
C) Herbivore size
D) Predator size
E) Climate

Question 12

Which trophic level would contain the lowest quantity of energy (kcal per m²)?

A) Secondary consumers
B) Tertiary consumers
C) Herbivores
D) Producers
E) Primary consumers

Question 13

Which statement about food chains is FALSE?

A) Owl consumption of mice benefits grasses.
B) Mice consumption of grasses is harmful to the grass population.
C) Owl consumption of mice harms grasses.
D) Owls are acting as secondary consumers when they eat mice.
E) Mice are herbivores.

Question 14

Approximately what proportion of the radiant energy entering an ecosystem is used in photosynthesis?

A) 1%
B) 4%
C) 10%
D) 50%
E) 75%

Question 15

Arrange the following from the ecosystem with the smallest average NPP to the ecosystems with the largest NPP. (1) Lake
(2) Savannah
(3) Estuary
(4) Tropical rain forest
(5) Open ocean

A) 1, 2, 3, 4, 5
B) 2, 1, 4, 3, 5
C) 2, 1, 5, 3, 4
D) 5, 2, 1, 3, 4
E) 5, 1, 2, 3, 4

Question 16

A food web is a more realistic depiction than a food chain because

A) organisms rarely eat just one kind of food.
B) energy flow is linear.
C) energy flow is cyclic.
D) a more complex model is always better than a simple one.
E) matter cycles in ecosystems.

Question 17

Which statement about biomass is FALSE?

A) Biomass reduction from one trophic level to the next is approximately 50%.
B) Biomass reduction from one trophic level to the next varies widely in nature.
C) Biomass reduction can be measured as dry weight.
D) Biomass may be measured as live weight.
E) Biomass in an ecosystem can be illustrated using a pyramidal-shaped graph.

Question 18

GPP, or Gross Primary Productivity

A) is the energy that remains in a plant after photosynthesis.
B) is the total energy captured from the sun through photosynthesis.
C) is the rate at which excess plant energy is converted to tissue for growth.
D) is the amount of energy available for primary consumers.
E) represents approximately 80% of the energy captured from the sun.

Question 19

Which statement about decomposers is FALSE?

A) They act with detritivores to break down and recycle organic matter.
B) They are microbial heterotrophs.
C) They include bacteria but not fungi.
D) They use the products of decomposition to supply themselves with energy.
E) They are also called saprotrophs.

Question 20

Pyramids of numbers are of limited usefulness because they

A) do not indicate the biomass of the organisms at a given time.
B) do not indicate the gross primary productivity of each species.
C) do not include energy flow through the ecosystem.
D) include three trophic levels.
E) have limited reliability of the actual numbers involved.

Question 21

Bacteria are most essential in the cycling of

A) carbon.
B) water.
C) phosphorus.
D) nitrogen.
E) energy.

Question 22

A primary source of carbon for photosynthetic organisms is

A) carbon dioxide in the atmosphere and water.
B) bicarbonate in the water.
C) nitrate in the soil.
D) dissolved phosphate in water.
E) carbonic acid in rain.

Question 23

Which is the greatest sink of phosphorus?

A) Mineable phosphate rocks
B) Atmosphere
C) Marine sediments
D) Soil phosphates
E) Marine organisms

Question 24

Which of the following processes restores nitrogen to the air?

A) Ammonification
B) Nitrification
C) Denitrification
D) Renitrification
E) Nitrogen fixation

Question 25

Four of the five statements listed below apply to the types of ecological pyramids. Which one is TRUE?

A) A pyramid of numbers is the most useful of the ecological pyramids.
B) A pyramid of energy shows that energy decreases as one goes toward the apex of the pyramid.
C) A pyramid of biomass cannot be inverted.
D) The base of all ecological pyramids is equal in size to the top.
E) The pyramid of numbers shows actual energy reduction from one trophic level to the next.

Question 26

Which process does not return carbon to the atmosphere?

A) Animal respiration
B) Photosynthesis
C) Combustion
D) Plant respiration
E) Decomposition

Question 27

The event in human history that changed the natural balance of the carbon cycle was the

A) Industrial Revolution.
B) Agricultural Revolution.
C) evolution of primates.
D) invention of farming.
E) invention of the telegraph.

Question 28

Transpiration is most closely associated with

A) the atmosphere.
B) terrestrial plants.
C) the ocean.
D) groundwater.
E) bacteria.

Question 29

The major components of Earth's atmosphere, from the lowest concentration to the greatest concentration, are

A) carbon dioxide, oxygen, and nitrogen.
B) carbon dioxide, nitrogen, and oxygen.
C) nitrogen, oxygen, and carbon dioxide.
D) nitrogen, carbon dioxide, and oxygen.
E) oxygen, nitrogen, and carbon dioxide.

Question 30

Fossil fuels, such as coal and oil, are derived from which biogeochemical cycle?

A) The hydrological cycle
B) The phosphorous cycle
C) The carbon cycle
D) The oxygen cycle
E) The nitrogen cycle

Question 31

Which process plays the most important role in the phosphorous cycle?

A) Cell respiration
B) Evaporation
C) Erosion
D) Combustion
E) Transpiration

Question 32

Since 1750, which of the following has/have absorbed the most carbon dioxide from the atmosphere?

A) Terrestrial plants
B) Soil
C) Glaciers
D) Rivers and streams
E) Oceans

Question 33

The effect of DDT on birds is a result of which three characteristics of DDT?

A) Metabolism, persistence, and biological magnification
B) Bioaccumulation, metabolism, and resistance
C) Biological magnification, resistance, and persistence
D) Persistence, bioaccumulation, and biological magnification
E) Metabolism, resistance, and biological magnification

Question 34

The main steps of the nitrogen cycle are

A) nitrogen fixation, nitrification, assimilation, digestion, and denitrification.
B) nitrigenation, nitrification, assimilation, ammonification, and denitrification.
C) nitrogen fixation, nitrification, assimilation, ammonification, and denitrification.
D) nitrogen fixation, nitrification, assimilation, carbonation, and denitrification.
E) nitrogen fixation, oxidation, assimilation, ammonification, and denitrification.

Question 35

Which process is not involved in the hydrologic cycle?

A) Nitrification
B) Transpiration
C) Precipitation
D) Evaporation
E) Condensation

Question 36

Dissolved phosphorus in aquatic ecosystems may return to the land via

A) erosion.
B) phosphate mining.
C) birds eating fish and mollusks.
D) zooplankton.
E) decomposition.

Question 37

What is the third trophic level of a food chain?

A) Primary consumers
B) Tertiary consumers
C) Autotrophs
D) Secondary consumers
E) Primary producers

Question 38

Fixation of carbon is accomplished by

A) photosynthetic organisms.
B) primary consumers.
C) decomposers.
D) bacterial decomposers.
E) burning of organic matter.

Question 39

To date, humans have interfered with all of the biogeochemical cycles on Earth, but this interference has been of the greatest magnitude, in terms of human-induced changes in climate, in the

A) hydrologic cycle.
B) nitrogen cycle.
C) carbon cycle.
D) sulfur cycle.
E) phosphorus cycle.

Question 40

What ecosystem has the highest rate of primary productivity?

A) Savanna
B) Agricultural land
C) Algal beds and reefs
D) Boreal forest
E) Tropical rain forest

Question 41

Which of the following directly drives ocean surface circulation patterns?

A) Solar energy
B) Salinity
C) Winds
D) Changes in water temperature
E) Coriolis effect

Question 42

How are bacteria important to the genus Rhizobium ?

A) They provide fixed carbon dioxide to legumes.
B) They provide fixed nitrogen to legumes.
C) They carry out photosynthesis.
D) They carry out respiration.
E) They carry out decomposition.

Question 43

The Coriolis effect results in the

A) rising of air at the equator.
B) falling of air near the poles.
C) deflection of moving air due to the rotation of Earth.
D) altitudinal variations in temperature.
E) release of heat once radiation strikes the Earth's surface.

Question 44

The enzyme nitrogenase is important in which part of the nitrogen cycle?

A) Ammonification
B) Denitrification
C) Nitrogen fixation
D) Assimilation
E) Decomposition

Question 45

In large measure, differences in ____ that are due to variations in the amount of _____ at different locations on Earth drive the circulation of the atmosphere.

A) temperature; rotation
B) rainfall; solar energy
C) temperature; radiation
D) temperature; rainfall
E) Temperature; evaporation

Question 46

Solar radiation

A) powers the hydrologic and other biogeochemical cycles.
B) is essential for chemosynthesis.
C) is the product of a massive nuclear fission event.
D) is eventually released from fossil fuels.
E) is eventually released via decomposition.

Question 47

The clockwise gyre of surface ocean currents in the North Atlantic results in

A) warmer water on Atlantic beaches of North America than Pacific beaches of the same latitude.
B) cooler water on Atlantic beaches of North America than Pacific beaches of the same latitude.
C) a clockwise gyre in the South Atlantic.
D) a circumpolar flow of water in the Northern Hemisphere.
E) prevailing trade winds.

Question 48

Bacterial decomposition of organic nitrogen results in the production of

A) ammonia.
B) nitrates.
C) nitrites.
D) atmospheric nitrogen.
E) urea.

Question 49

On average, clouds and surfaces, especially snow, ice, and the ocean, immediately reflect away ____% of the solar radiation that falls on Earth.

A) 10
B) 20
C) 30
D) 50
E) 70

Question 50

During the cycling of phosphorus, which biological process is critical in cycling dissolved phosphorus?

A) Photosynthesis
B) Decomposition
C) Mitosis
D) Meiosis
E) Respiration

Question 51

The 'sun's energy is produced by

A) nuclear fission reactions.
B) nuclear fusion reactions.
C) electromagnetic radiation.
D) ultraviolet radiation.
E) infrared radiation.

Question 52

Which issue is least likely to have been the result of human impact on the nitrogen cycle?

A) Photochemical smog
B) Global warming
C) Acid rain
D) El Niño-Southern Oscillation events
E) Depletion of the ozone layer

Question 53

Nitrogen is a critical requirement for living organisms because it is a component of

A) carbohydrates and lipids.
B) carbohydrates.
C) lipids and nucleic acids.
D) nucleic acids and proteins.
E) nucleic acids and carbohydrates.

Question 54

The ultimate source of energy for the communities of the hydrothermal vents is provided by

A) hot seawater.
B) sinking detritus from the surface waters.
C) photosynthesis.
D) chemoautotrophic prokaryotes.
E) radioactive rocks.

Question 55

Which step of the nitrogen cycle is not performed by most bacteria?

A) Ammonification
B) Denitrification
C) Assimilation
D) Nitrogen fixation
E) Nitrification

Question 56

The primary reason that Earth experiences seasons is because of the

A) Earth's rotation.
B) Earth's orbit.
C) Earth's tilt on its axis.
D) unequal thickness of the Earth's atmosphere.
E) different layers of the Earth's atmosphere.

Question 57

Which nutrient cycle does not have a gaseous phase?

A) Hydrologic cycle
B) Nitrogen cycle
C) Carbon cycle
D) Sulfur cycle
E) Phosphorus cycle

Question 58

Nitrogen-fixing bacteria convert gaseous nitrogen into

A) amino acids.
B) phosphate.
C) ammonia.
D) nitrite.
E) nitrate.

Question 59

Plant roots absorb nitrate or ammonia and incorporate these compounds into plant proteins via the process of

A) ammonification.
B) denitrification.
C) assimilation.
D) nitrogen fixation.
E) nitrification.

Question 60

Denitrifying bacteria

A) make nitrogen available for assimilation.
B) decompose organic nitrogen compounds into nitrate.
C) decompose organic nitrogen compounds into ammonia.
D) fix nitrogen into ammonia.
E) convert nitrate into atmospheric nitrogen.

Question 61

Drier climates tend to prevail

A) on the windward side of mountains.
B) in a rain shadow.
C) close to the coast of the continent.
D) in temperate regions.
E) only in the Northern Hemisphere.

Question 62

What two abiotic factors are considered to most affect organisms?

A) Fire and water
B) The atmosphere and fire
C) Temperature and fire
D) Temperature and water
E) Climate and fire

Question 63

How does temperature changes with respect to latitude and season?

Question 64

The buildup of a toxin in an organism's body is called biological magnification.

Question 65

A decomposer is also called a saprotroph.

Question 66

Gross primary productivity is the rate of photosynthesis minus the rate of plant respiration.

Question 67

An herbivore occupies the third trophic level.

Question 68

Identify and describe three beneficial impacts of fire on certain ecosystems.

Question 69

What did Stephen Carter and his team from University of Madison-Wisconsin study?

A) Salt water intrusion into estuaries
B) Tipping points for endangered food webs
C) Acidification of ocean ecosystems
D) Effects of dams on river flow
E) Desertification of dune ecosystems

Question 70

Briefly describe where deserts develop and why.

Question 71

Algae and cyanobacteria are examples of primary consumers.

Question 72

Which process is NOT indirectly related to absorption of solar energy by the Earth's surface?

A) Water cycle
B) Photosynthesis
C) Winds
D) Surface currents
E) Coriolis effect

Question 73

In a food chain, producers occupy the first trophic level.

Question 74

The organisms that feed from all trophic levels are secondary consumers.

Question 75

What is the least likely effect of fires on organisms?

A) Fire stimulates the germination of seeds.
B) Fire's combustion frees minerals locked in organic matter.
C) Fire instigates the growth of shade-tolerant plants.
D) Fire encourages the growth of shade-intolerant plants.
E) Fire increases soil erosion.

Question 76

The atmosphere performs several essential ecological functions. One of these is to

A) protect Earth from all infrared radiation.
B) reduce the amount of visible light reaching Earth.
C) provide plants with nitrogen needed for photosynthesis.
D) protect Earth from microwave radiation.
E) protect Earth from most ultraviolet radiation.

Question 77

Briefly discuss which biogeochemical cycle produces photochemical smog and why it is hazardous.

Question 78

In the carbon cycle, one of the ways in which carbon is returned to the atmosphere is by respiration.

Question 79

Consider a deciduous forest and its pyramid of biomass. Why are a large number of berry plants necessary to support a population of foxes?

Question 80

Nitrogen fixation is the process by which gaseous nitrogen is converted to nitrate.