Deck 18: Ecosystems

Question 1

Which of the following series best represents the energy flow in an ecosystem?

A)sun ® consumer ® producer ® metabolic heat
B)consumer ® producer ® decomposer ® sun
C)producer ® consumer ® decomposer ® sun
D)sun ® producer ® consumer ® metabolic heat

Answer 1

D

Question 2

Which of the following groups of organisms would NOT be considered to be consumers?

A)herbivores
B)predators
C)decomposers
D)photosynthesizers

Answer 2

D

Question 3

What would happen to nutrient cycling in a forest ecosystem if all of the bacteria,protozoans,fungi,and worms were eliminated?

A)Dead plant and animal matter would accumulate more quickly than it is decomposed,and the soil would become depleted of nutrients.
B)Dead plant and animal matter would decay more rapidly than it is decomposed,and the soil would accumulate nutrients at a faster rate.
C)There would be no discernable change in the rate at which dead plants and animals decompose and no change in the rate of nutrient accumulation in the soil.
D)Dead plant and animal matter would accumulate more quickly than it is decomposed,and the soil would accumulate nutrients at a faster rate.

Answer 3

A

Question 4

The primary contribution of decomposers to an ecosystem occurs when they

A)capture solar energy.
B)recycle nutrients sequestered in organisms back to the physical environment.
C)regulate the number of producers.
D)prevent consumer overpopulation.

Question 5

Which of the following would be abiotic components of an arctic,marine ecosystem?

A)saltwater,ice,snow,sun,wind,rocks,sand
B)polar bears,seals,salmon,seaweed,puffins
C)buffalo,meadowlarks,eagles,grasses,cottonwood trees
D)deer,skinks,squirrels,oak trees,pine trees,mosses

Question 6

You are relaxing on an island beach enjoying the warm air and sunshine when you notice the striking pure blue color of the water in the deep crater of the island's bay.The water in the surrounding ocean is more of a green color.Which of the following is a logical hypothesis?

A)The water in the bay has a low level of phytoplankton while there is a higher concentration of phytoplankton in the surrounding ocean.
B)The water in the bay has a high level of phytoplankton while there is a lower concentration of phytoplankton in the surrounding ocean.
C)The concentration of phytoplankton in the bay and the surrounding ocean is the same,and it is very high.
D)The concentration of phytoplankton in the bay and the surrounding ocean is the same and is almost zero.

Question 7

Within the ecosystem,nutrients

A)move in a one-way path from producers toward consumers.
B)regularly cycle between organisms and the nonliving environment.
C)are consumed by their use and thus are not available for recycling.
D)are rarely limiting because they are constantly replenished as the Earth's crust is eroded.

Question 8

In an ecosystem,energy differs from nutrients in that

A)energy is recycled through photosynthesis,but nutrients are recycled through the atmosphere.
B)nutrients are recycled,but energy eventually moves out of the system and is lost.
C)nutrients are recycled through plant roots,but energy is recycled through leaves.
D)energy is recycled by producers,but nutrients are recycled by consumers.

Question 9

Which of the following are likely biotic components of a desert ecosystem?

A)sand,sun,and occasional rain
B)cacti,sage brush,scorpions,and snakes
C)oak trees,rhododendrons,squirrels,and moss
D)moss,large pine trees,frogs,and otters

Question 10

Which of the following statements about cycling within an ecosystem is FALSE?

A)Energy is recycled within an ecosystem.
B)Carbon is recycled within an ecosystem.
C)The sedimentary nutrient cycle cycles nutrients very slowly.
D)Human activities affect nutrient cycling.

Question 11

In the absence of ________,nutrient recycling within the ecosystem would completely stop.

A)rocks
B)secondary consumers
C)decomposers
D)predators

Question 12

Rabbits,foxes,tapeworms,and fungi are all examples of

A)consumers.
B)primary producers.
C)abiotic ecosystem components.
D)photosynthesizers.

Question 13

A community of organisms together with the physical environment in which they live is known as a(n)

A)population.
B)community.
C)ecosystem.
D)biota.

Question 14

Areas of the ocean that are very cloudy due to large amounts of stirred sediment or eroded soil are likely to

A)experience decreased primary productivity levels.
B)experience increased primary productivity levels.
C)experience no change in primary productivity levels.
D)experience an increase in primary productivity levels with a decrease in secondary productivity levels.

Question 15

Which of the following are examples of primary producers in a beech-maple woodland?

A)mosses,grasses,beech trees,maple trees
B)phytoplankton and seaweed
C)phytoplankton,reeds,marsh grasses
D)squirrels,skinks,deer,and opossums

Question 16

Ecologists often define an ecosystem by describing how ________ and ________ are acquired and distributed by the biotic community.

A)energy;nutrients
B)producers;consumers
C)decomposers;consumers
D)nutrients;producers

Question 17

All of the living organisms present in an ecosystem comprise the ________ or biotic portion of the ecosystem.

A)community
B)abiotic
C)population
D)biome

Question 18

The chemical and physical components of an ecosystem are considered to be ________ or nonliving.

A)abiotic
B)biota
C)biotic
D)abalone

Question 19

Almost all life on Earth is directly or indirectly dependent on

A)solar energy.
B)predation.
C)physical productivity.
D)human civilization.

Question 20

A tallgrass prairie or beech-maple woodland are examples of

A)ecologists demarcating an ecosystem according to the types of producers it contains;this,in turn,establishes the type of consumers that the ecosystem supports.
B)ecologists demarcating an ecosystem according to the climate in which it is located.
C)ecologists demarcating an ecosystem according to the type of consumers it contains;this,in turn,establishes the type of producers that the consumers support.
D)ecologists demarcating an ecosystem according to the daily rainfall amounts;this does not affect the types of consumers or producers present in the ecosystem.

Question 21

In the absence of ________,nutrients would not move from the abiotic to the biotic portion of the nutrient cycle within an ecosystem.

A)primary producers
B)herbivores
C)carnivores
D)omnivores

Question 22

You are studying a grassland ecosystem with 400,000 kcal of energy stored in the primary producer level.Grasshoppers eat the grass,meadowlarks eat the grasshoppers,and a hawk eats the meadowlarks.How many kcals are now stored,and available,in the hawk?

A)40,000
B)4,000
C)400
D)40

Question 23

On average,what percentage of the energy from one trophic level of an energy pyramid is transferred to the next trophic level?

A)10 percent
B)33 percent
C)50 percent
D)90 percent

Question 24

If there are 5,000,000 kcal of energy stored in grain that could be fed either to beef cattle or humans and you choose to feed the grain to the cattle to fatten them up for the humans,how many kcal would now be available as beef to feed the humans?

A)500,000
B)50,000
C)5,000
D)500

Question 25

When humans consume rice they occupy which trophic level of a food chain?

A)primary consumer
B)secondary consumer
C)tertiary consumer
D)primary producer

Question 26

Tuna are predatory fish that consume smaller,carnivorous fish that have fed on zooplankton.The zooplankton had fed on phytoplankton.You eat tuna,you are what level of the food chain?

A)the second trophic level
B)the third trophic level
C)the fourth trophic level
D)the fifth trophic level

Question 27

In the diagram below,how do nutrient and energy flow differ?

A)Energy flow is one-way,whereas nutrients are recycled.
B)Energy is recycled,whereas nutrient flow is one-way.
C)Only about 10 percent of energy flows from trophic level to trophic level.Nutrient flow is 100 percent from trophic level to trophic level.
D)Energy flows only to primary producers and decomposers,whereas nutrients flow only to secondary consumers and decomposers.

Question 28

Human activities

A)rarely affect nutrient cycles.
B)can alter nutrient cycles on local and global scales.
C)tend to cause only local changes in nutrient cycles.
D)generally improve nutrient cycling in ecosystems.

Question 29

If a person needs to consume 100 kcal of energy and she chooses to do that by eating chicken,how many kcal of grain would the chicken need to consume to make 100 kcal available to the human?

A)1,000 kcal
B)10,000 kcal
C)100,000 kcal
D)1,000,000 kcal

Question 30

What is the primary difference between consumers and decomposers?

A)Consumers obtain their nutrients by eating other live organisms while decomposers obtain their nutrients from dead consumers.
B)Consumers obtain their nutrients by eating only dead consumers while decomposers eat other live consumers.
C)Consumers and decomposers both obtain all of their nutrients from eating other live organisms.
D)Consumers obtain their nutrients by eating other live organisms while decomposers obtain their nutrients through photosynthesis.

Question 31

If there are 50 kcal of energy in the tertiary consumer trophic level,how many kcal would you expect to find in the primary consumer level?

A)50
B)100
C)500
D)5,000

Question 32

Energy does not cycle through an ecosystem.This is because energy enters an ecosystem through photosynthesis as it changes to chemical energy.This is then used to fuel metablic activities

A)in plants only,and all of the excess energy is lost as metabolic heat.
B)in consumers only,and all of the excess energy is lost as metabolic heat.
C)in decomposers only,and all of the excess energy is lost as metabolic heat.
D)in producers,consumers,and decomposers,and all of the excess energy is lost as metabolic heat.

Question 33

If a person needs to consume 100 kcal of energy and he chooses to do that by eating soybeans,at least how many kcal of soybeans would have to grow to provide that 100 kcal for the human?

A)100 kcal
B)1,000 kcal
C)10,000 kcal
D)100,000 kcal

Question 34

Your spacecraft crash-lands on an airless,lifeless moon.All that survives,along with the crew and you,are some chickens,cornflakes,and vitamins.The air and water recyclers are functioning.To maximize the food supply until a rescue craft arrives,you and the crew should

A)feed the cornflakes and vitamins to the chickens,then eat the eggs until rescued.
B)kill all the chickens immediately,eat them first,then eat the cornflakes.
C)mark each week's survival by eating one chicken.
D)ration the chickens first.When they are all eaten,shift to the cornflakes.

Question 35

Tuna are predatory fish that consume smaller,carnivorous fish that have fed on zooplankton.The zooplankton had fed on phytoplankton.When you eat tuna,you are consuming what level of the food chain?

A)the second trophic level
B)the third trophic level
C)the fourth trophic level
D)the first trophic level

Question 36

If there are 5,000,000 kcal of energy stored in grain that could be fed either to chickens or humans and there is a small village of starving people that need to be fed,what is the most efficient way to feed the majority of the villagers?

A)Feed all of the grain to the villagers.
B)Feed all of the grain to chickens and let the villagers eat the eggs.
C)Feed all of the grain to chickens and let the villagers eat the chickens.
D)Feed some of the grain to chickens and some of it to villagers.

Question 37

If there are 20,000 kcal available in the primary producer level of an ecosystem,how many kcal would be available in the secondary consumer level?

A)200 kcal
B)20 kcal
C)2 kcal
D)2,000 kcal

Question 38

Which of the following describes the ultimate disposition of most energy in an ecosystem?

A)It is used to construct the bodies of decomposers.
B)It is trapped as fossil fuels when producers die and become fossilized.
C)It is continuously recycled back into the ecosystem.
D)It eventually returns to space in the form of heat.

Question 39

How might a decline in phytoplankton affect the climate of Earth?

A)A decline in phytoplankton could alter the carbon cycle by moving less carbon dioxide from the atmosphere into phytoplankton tissues.Since carbon dioxide is a greenhouse gas,more of it in the atmosphere could contribute to global warming.
B)A decline in phytoplankton could alter the phosphorous cycle by moving less phosphorous from the atmosphere into phytoplankton tissues.Since phosphorous is a greenhouse gas,more of it in the atmosphere could contribute to global warming.
C)A decline in phytoplankton could alter the hydrologic cycle by moving less water from the atmosphere into phytoplankton tissues.Since water is a greenhouse gas,more of it in the atmosphere could contribute to global warming.
D)A decline in phytoplankton could alter the oxygen cycle by moving less oxygen from the atmosphere into phytoplankton tissues.Since oxygen is a greenhouse gas,more of it in the atmosphere could contribute to global warming.

Question 40

When humans consume herbivores such as cattle,they occupy which trophic level of a food chain?

A)primary consumer
B)secondary consumer
C)tertiary consumer
D)primary producer

Question 41

What best explains this observation: consumers directly use approximately 20 percent of a forest's net primary productivity (NPP),whereas decomposers directly use approximately 80 percent?

A)Decomposers are more efficient at obtaining energy than consumers.
B)Forest ecosystems do not have a very high NPP,so they cannot support as many consumers as other ecosystems can.
C)Consumers eat only certain parts of organisms,such as fruits or muscle tissue,whereas decomposers obtain energy from the entire body of the food organism.
D)Secondary consumers eat the primary consumers more quickly than the primary consumers can eat the producers,thus leaving most of the NPP available to the decomposers.

Question 42

Other than tropical forests,the most productive biomes tend to be

A)estuaries.
B)deep oceans.
C)deserts.
D)tundras.

Question 43

The figure below shows the net primary productivity (NPP)in terrestrial biomes around the world.The pattern of NPP in terrestrial ecosystems as shown suggest that

A)terrestrial productivity is highly sensitive to temperature and available sunlight with the highest productivity at the equator.
B)without shade from overhead vegetation,marine productivity typically exceeds that found in terrestrial ecosystems.
C)terrestrial ecosystems are not limited by sunlight or temperature.
D)most terrestrial productivity results from the input of marine-derived nutrients.

Question 44

The figure below shows the net primary productivity (NPP)in marine biomes around the world.The pattern of NPP in marine ecosystems as shown suggests that

A)marine productivity is as sensitive to temperature as terrestrial productivity.
B)without shade from overhead vegetation,marine productivity typically exceeds that found in terrestrial ecosystems.
C)marine ecosystems are also limited by sunlight,with the highest productivity at the equator.
D)most marine productivity results from the input of terrestrially derived nutrients.

Question 45

Describe how chemical nutrients enter and are recycled through an ecosystem.

Question 46

On what four factors does net primary productivity rely,and what terrestrial ecosystem is the most productive because of these factors?

Question 47

Which of the following is NOT an easily testable hypothesis regarding net primary productivity?

A)An increase in temperature will likely result in an increase of net primary productivity (NPP)in some terrestrial ecosystems.
B)An increase in temperature will likely result in an increase of NPP in some marine ecosystems.
C)An increase in available sunlight will likely result in an increase of NPP in some marine and terrestrial ecosystems.
D)An increase of water in a marine ecosystem will likely result in tastier products of NPP.

Question 48

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
Found at the poles and on mountaintops,the vegetation of this biome is dominated by low-growing flowering plants,and the rock landscape is covered in mosses and lichens.Rodents provide food for carnivores like foxes and wolves.The few large mammals include bears and musk oxen.

Question 49

A group of living communities interacting with one another and their shared physical environment is a(n)________.

Question 50

An ecosystem that experiences a small increase in nutrients available to primary producers is likely to show

A)an increase in net primary productivity.
B)a decrease in net primary productivity.
C)no change in net primary productivity.
D)a decrease in net primary productivity followed by an immediate return to average net primary productivity.

Question 51

Why are deserts and tundra among the least productive terrestrial biomes?

A)Water is not very easily accessible by plants in desert and tundra biomes,and both of these biomes experience extreme temperature conditions.Water availability and temperature are important limiting factors in net primary productivity (NPP).
B)There is too much water available in the tundra and not enough available in the desert.The extreme temperatures of these biomes do not affect NPP.
C)There is not enough sunlight available in either the tundra or the desert biomes to sufficiently support NPP.
D)There is far too much sunlight and water available in both the desert and tundra biomes.These factors cause photosynthesis to be suspended and result in dramatically decreased NPP.

Question 52

To best use the Earth's net primary productivity to feed the most people,diets should be modified to include ________,and gathering the maximum amount of energy available from a given biomass of producers.

A)only meat,moving higher up the food chain
B)only meat,moving lower down the food chain
C)plant material only,moving lower down the food chain
D)plant material only,moving higher up the food chain

Question 53

The amount of energy captured by photosynthetic organisms,minus the amount lost as heat from respiration and other life processes,is called ________.

Question 54

Each level of an energy pyramid corresponds to a step in a food chain and is called a(n)________ level.

Question 55

Other than the polar tundra,the LEAST productive terrestrial biomes tend to be

A)deserts.
B)the temperate forests.
C)the tropical forests.
D)estuaries.

Question 56

Producers capture energy from the ________ and transform it into fuel energy that passes up the food chain as one organism eats another.

Question 57

Between late 1997 and mid-2008,satellites observed that warmer-than-average ocean temperatures led to below-average chlorophyll concentrations in the oceans.This finding suggests that continued warming of the Earth's oceans could lead to

A)a decrease in net primary productivity in the oceans,and the oceans would,therefore,remove less carbon dioxide from the atmosphere.
B)an increase in net primary productivity in the oceans,and the oceans would,therefore,remove less carbon dioxide from the atmosphere.
C)a decrease in net primary productivity in the oceans,and the oceans would,therefore,remove more carbon dioxide from the atmosphere.
D)an increase in net primary productivity in the oceans,and the oceans would,therefore,remove more carbon dioxide from the atmosphere.

Question 58

Considering this food chain,explain how many calories are available in the consumer trophic levels and why.

Question 59

In marine ecosystems,net primary productivity tends to be

A)greater along shorelines where terrestrial nutrients enter the marine environment.
B)lower where the oceans border land because terrestrial pollution suppresses marine productivity.
C)lowest in areas where upwelling brings colder water to the surface.
D)greater than the net primary productivity on land.

Question 60

Explain why ecosystems do not always have sharply defined physical boundaries.

Question 61

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
This biome is commonly found in both temperate and tropical latitudes.It does not receive enough moisture to support vigorous tree growth,so it is dominated by grasses and herbaceous plants.Burrowing rodents like voles and prairie dogs are common.

Question 62

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
This biome is dominated by dense growths of drought-resistant plants that thrive through the alternating cool,rainy winters and hot,dry summers.The vegetation includes scrub oak,pines,mountain mahogany,and manzanita.It is inhabited by jackrabbits,gophers,lizards,and snakes.

Question 63

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
Dominated by coniferous trees that grow in northern or high-altitude regions with cold,dry winters and mild summers,this biome also has nutrient-poor soils and therefore a relatively low plant diversity.Large herbivores such as elk and moose live alongside smaller carnivores like weasels,wolverines,and martens.Larger carnivores include lynx and wolves.

Question 64

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
This biome is dominated by trees and shrubs adapted to relatively rich soil,snowy winters,and moist,warm summers.With oak,maple,hickory,beech,and elm,this biome displays good diversity.Squirrels,rabbits,deer,raccoons,beavers,bobcats,mountain lions,bears,and many amphibians and reptiles constitute the consumer community.

Question 65

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
Nearly one third of the Earth's land surface is covered with this biome that does not retain heat because it lacks moisture.The plants have small leaves,like the spines on cacti,to minimize water loss.Most of the animals are nocturnal.

Question 66

Match each term to its correct description below.
a.tropical forest
b.chaparral
c.boreal forest
d.tundra
e.desert
f.temperate deciduous forest
g.grassland
Characterized by warm temperatures and roughly 12 hours of daylight all year,this biome receives either seasonally heavy rains or year-round rains that leach nutrients from the soil.Much of the soil nutrients are locked up in the biomass of the heavy vegetation.This biome is one of the most richly biodiverse and productive ecosystems on the planet.