Deck 55: Ecosystems and the Biosphere

Question 1

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.

Answer 1

A

Question 2

Which of the following statements 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 2

B

Question 3

Select the false statement:

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 3

A

Question 4

Which of the following are likely detritivores?

A) earthworms
B) deer
C) grasshoppers
D) spiders
E) lions

Question 5

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) None of the answer choices is correct.

Question 6

Which statement 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 of the following terms is synonymous with 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 8

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 9

Which of the following does not represent a form of energy that can commonly be found in an ecosystem?

A) work, such as reproduction
B) ATP
C) heat
D) ammonia
E) glucose

Question 10

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 11

Which of the following statements concerning 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 12

What biome has the highest rate of primary productivity?

A) savanna
B) tundra
C) algal beds and reefs
D) temperate grassland
E) tropical rain forest

Question 13

In an ecosystem, which measure of energy is necessarily 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 14

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

A) secondary consumers
B) tertiary consumers
C) herbivores
D) producers
E) primary consumers

Question 15

Figure 55-1
Use the figure to answer the corresponding question(s).
Figure 55-1 represents:

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

Question 16

Figure 55-1
Use the figure to answer the corresponding question(s).
The distribution in Figure 55-1 could be inverted:

A) if the producers had a high rate of productivity and reproduction, coupled with intense predation.
B) if the rate of biomass production of the primary consumers is greater than that of the producers.
C) if the rate of productivity of the primary consumers is greater than the primary productivity.
D) if the standing biomass of the producers is greater than the biomass of all of the consumers.
E) only under artificial or laboratory conditions.

Question 17

Figure 55-2
Use the figure to answer the corresponding question(s).
Figure 55-2 is a good illustration of:

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

Question 18

Arrange the following from the ecosystem with the smallest average NPP to the ecosystems with the largest NPP. 1)
Lake
2)
Savanna
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 19

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 20

A linear depiction of energy flow in an ecosystem is:

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

Question 21

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 22

Carbon can be returned to the atmosphere by all of the following except:

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

Question 23

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 24

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 25

Which of the following processes plays an important role in the phosphorous cycle?

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

Question 26

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

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

Question 27

Fixation of carbon is accomplished by:

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

Question 28

Bacterial decomposition of organic nitrogen results in the production of:

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

Question 29

Bacteria are most essential in the cycling of:

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

Question 30

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) decompostion.

Question 31

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 32

What is the significance of bacteria in 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 33

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

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

Question 34

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 35

Nitrogen-fixing bacteria convert gaseous nitrogen into:

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

Question 36

All of the following problems are direct results of human impact on the nitrogen cycle except:

A) photochemical smog.
B) global warming.
C) acid rain.
D) El Niño-Southern Oscillation events.
E) depletion of the ozone layer.

Question 37

The major atmospheric components of Earth, 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 38

This nutrient cycle does not have a gaseous phase:

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

Question 39

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 40

Figure 55-2
Use the figure to answer the corresponding question(s).
In Figure 55-2, 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 41

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 42

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 43

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

Question 44

Compare and contrast the conceptual foundation and application of two different types of ecological pyramids.

Question 45

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 46

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 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

Fires may result in:

A) decreased erosional rates.
B) enrichment of the soil.
C) decreased soil fertility.
D) decreased evaporation from the soil surface.
E) increased amounts of organic litter on the soil.

Question 49

Which of the following processes is not involved in the hydrologic cycle?

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

Question 50

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 51

Transpiration occurs in:

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

Question 52

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 53

The two most important factors that determine an area's climate are:

A) temperature and wind.
B) humidity and temperature.
C) temperature and precipitation.
D) cloud cover and wind.
E) humidity and fog.

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) eel grass.

Question 55

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

Question 56

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

A) Coriolis effect
B) precipitation
C) biogeochemical cycles
D) sun
E) evaporation.

Question 57

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 58

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

Question 59

Effects of deforestation illustrated by the Hubbard Brooks Experimental Forest include all of the following except:

A) soil erosion.
B) leaching of essential nutrient minerals.
C) decreased soil fertility.
D) higher summer temperatures in previously shady streams.
E) acid deposition.

Question 60

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 61

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

Question 62

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

Question 63

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
the principle enzyme is nitrogenase

Question 64

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
carried out by nitrifying bacteria

Question 65

Algae and cyanobacteria are examples of primary producers.
____________________

Question 66

The most abundant gas in the atmosphere is oxygen.
____________________

Question 67

In the African savanna, fire helps maintain the dominant vegetation.
____________________

Question 68

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

Question 69

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

Question 70

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
returns gaseous nitrogen to the atmosphere

Question 71

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
the process by which animals convert plant nitrogen compounds into animal nitrogen compounds

Question 72

A decomposer is also called a saprotroph.
____________________

Question 73

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

Question 74

ENSO refers to a periodic warming of surface ocean waters.
____________________

Question 75

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
Rhizobium carries out this process

Question 76

The seasons are determined primarily by the Earth's tilt.
____________________

Question 77

MATCHING
Match the component of the nitrogen cycle with its description.
a.assimilation
c.nitrification
b.denitrification
d.nitrogen fixation
converts N₂ to NH₃

Question 78

One element that does not cycle into the atmosphere is phosphorus.
____________________

Question 79

An herbivore occupies the third trophic level.
____________________

Question 80

A rain shadow occurs in the dry lands on the sides of mountains facing the prevailing winds.
____________________