Deck 55: Ecosystems and the Biosphere

Question 1

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.

Answer 1

A

Question 2

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.

Answer 2

A

Question 3

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

Answer 3

A

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

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 6

Which statement about food chains is FALSE?

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

Question 7

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 8

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.

Question 9

Figure 55-1 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.

Question 10

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 11

Figure 55-2 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 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

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 14

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 15

Organisms that manufactures their own food are known as:

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

Question 16

Figure 55-2 The accompanying figure is a good illustration of:

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

Question 17

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 18

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 19

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) plant and animal respiration combined

Question 20

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 21

Four of the five statements below apply to the phosphorus cycle. Which one does not apply?

A) Phosphorus cycles from land to water and back again.
B) Phosphorus does not exist in a gaseous state.
C) Dissolved phosphorus enters aquatic ecosystems from the atmosphere.
D) Phosphorus will probably be depleted during the 21st century.
E) Erosion from clear-cutting and agriculture accelerate phosphorus loss.

Question 22

Which process is not involved in the hydrologic cycle?

A) nitrification
B) transpiration
C) precipitation
D) evaporation
E) condensation

Question 23

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 24

Transpiration is most closely associated with:

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

Question 25

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 26

Bacteria are most essential in the cycling of:

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

Question 27

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 28

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 29

Which process does not return carbon to the atmosphere?

A) animal respiration
B) photosynthesis
C) combustion
D) plant respiration
E) decomposition

Question 30

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 31

Four of the five answers listed below reflect how humans have disturbed the balance of the global nitrogen cycle. Which is the exception?

A) use of fertilizer
B) combustion of fossil fuels
C) airplane travel
D) coal-fired power plants
E) overuse of refrigerants

Question 32

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

A) A pyramid of numbers has the greatest number of organisms at the top.
B) A pyramid of energy shows that energy increases 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 biomass show actual biomass reduction from one trophic level to the next.

Question 33

Fixation of carbon is accomplished by:

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

Question 34

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 35

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 36

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 dinitrification.
D) nitrogen fixation, nitrification, assimilation, carbonation, and denitrification.
E) nitrogen fixation, oxidation, assimilation, ammonification, and denitrification.

Question 37

Since 1750, the main cause of increased carbon dioxide being released into the atmosphere is:

A) the burning of fossil fuels such as coal and gasoline.
B) the burning of wood.
C) cattle production.
D) erosion.
E) decomposition.

Question 38

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 39

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

A) cell respiration
B) evaporation
C) erosion
D) combustion
E) transpiration

Question 40

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 41

The enzyme nitrogenase is rather unique, as it specifically functions in the:

A) absence of oxygen.
B) absence of nitrogen.
C) absence of carbon dioxide.
D) presence of oxygen.
E) presence of carbon dioxide.

Question 42

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 43

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 44

Wind drives the ocean's currents and __________ drives wind.

A) the Coriolis Effect
B) precipitation
C) biogeochemical cycles
D) the sun
E) evaporation

Question 45

Bacterial decomposition of organic nitrogen results in the production of:

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

Question 46

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 47

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 48

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

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

Question 49

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 50

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 51

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 52

About __________ of the total energy the sun releases strikes the atmosphere.

A) one-tenth
B) one-hundredth
C) one-thousandth
D) one-millionth
E) one-billionth

Question 53

Nitrogen-fixing bacteria convert gaseous nitrogen into:

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

Question 54

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 55

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 56

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 57

El Niño-Southern Oscillation has resulted in:

A) global weather changes.
B) increases in the fish populations off South America.
C) cooling of surface waters of the East Pacific.
D) upwelling in many places.
E) global warming.

Question 58

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 59

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 60

During the cycling of phosphorus, phosphorus does not enter ____ in appreciable amounts.

A) the atmosphere
B) the groundwater
C) organisms
D) marine sediments
E) the ocean

Question 61

In considering a pyramid of biomass, explain why a large producer biomass is needed to support a population of carnivores.

Question 62

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 63

The organisms occupying the base of a pyramid of energy are autotrophs .
____________________

Question 64

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

Question 65

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

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

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 69

Explain how and why temperature changes with respect to latitude and with respect to season.

Question 70

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

Question 71

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

Question 72

A decomposer is also called a(n) saprotroph .
____________________

Question 73

Clearly differentiate between the following terms: gross primary productivity and net primary productivity.

Question 74

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 75

Algae and cyanobacteria are examples of primary producers .
____________________

Question 76

Which biogeochemical cycle produces photochemical smog and why is it a hazard?

Question 77

In a food chain, primary consumers occupy the firs t trophic level.
____________________

Question 78

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 79

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 80

Approximately ____ percent of the sun's energy is reflected back into space.

A) 10
B) 20
C) 30
D) 40
E) 50