Deck 57: Dynamics of Ecosystems

Question 1

The scarcity of which two elements limits plant growth?

A)oxygen, nitrogen
B)nitrogen, phosphorus
C)oxygen, phosphorus
D)carbon, nitrogen

Answer 1

B

Question 2

A wolf that feeds on moose and elk would be classified within which trophic level?

A)herbivore
B)primary producer
C)primary carnivore
D)secondary carnivore

Answer 2

C

Question 3

Over tropical rainforest areas, approximately 90% of the water that reaches the atmosphere comes from

A)animal metabolism.
B)animal perspiration.
C)plant transpiration.
D)plant absorption.

Answer 3

C

Question 4

A(n) ________ is a permeable underground layer of rock, sand, and gravel saturated with groundwater.

A)natural spring
B)aquifer
C)hot spring
D)submergence

Question 5

Which of the following groups do not contain any species that are autotrophs?

A)Bacteria
B)Protista
C)Plants
D)Archaea
E)Fungi

Question 6

The balance between photosynthesis and ___________ is altered by the combustion of fossil fuels.

A)respiration
B)sunlight
C)growth
D)decomposition

Question 7

Only about ____ of the sunlight falling on plant leaves is captured by photosynthesis.

A)1%
B)10%
C)25%
D)50%

Question 8

Heterotrophs must obtain organic molecules that have been synthesized by

A)biogeochemical cycles.
B)bacteria.
C)decomposers.
D)autotrophs.

Question 9

In the carbon cycle, ______ from the atmosphere is used in photosynthesis to synthesize carbon-containing organic molecules in a process called ______.

A)carbon dioxide; combustion
B)carbon dioxide; carbon fixation
C)hydrocarbons; oxidation
D)hydrocarbons; cellular respiration

Question 10

Which of the following atmospheric gas is changing the global climate?

A)ozone
B)water vapor
C)carbon dioxide
D)hydrogen

Question 11

The form of nitrogen most likely to be absorbed from the soil by plants is

A)nitrogenous wastes.
B)nucleic acids.
C)nitrogen gas.
D)nitrous oxide gas.
E)nitrite/nitrate ions.

Question 12

With almost no exceptions, the nitrogen fixers are

A)beans.
B)green plants.
C)insects.
D)mammals.
E)prokaryotes.

Question 13

Which of the following biogeochemical cycles contain a mineral component?

A)phosphorus
B)carbon
C)nitrogen
D)oxygen

Question 14

The upper, unconfined portion of the groundwater constitutes the ____, which flows into streams and is partly accessible to plants.

A)aquifer
B)hydrozone
C)water table
D)watershed

Question 15

Vampire squid (Vampyroteuthisinfernalis) are deep-sea cephalopods with features similar to both octopus and squid.Extensive video recordings show the diet of the vampire squid consists of items like crustacean remains and fecal pellets.Which of the following terms describes the position of the vampire squid in the deep-sea trophic pyramid?

A)herbivore
B)primary producer
C)primary carnivore
D)secondary carnivore
E)detritivore

Question 16

A ____________ cycle is a cyclic path that involves both biological and chemical processes of an ecosystem.

A)biogeochemical
B)complete
C)hydrological
D)complementary

Question 17

Even though nitrogen constitutes 78% of Earth's atmosphere, the amount available for living things nearly all comes from

A)a few groups of nitrogen-fixing bacteria.
B)the breakdown of minerals.
C)a few genera of detritivores.
D)the breakdown of dead plants.

Question 18

NPP is the difference between plant photosynthesis and respiration.Therefore, NPP quantifies the net absorption of what element(s) by living plants?

A)carbon
B)phosphorus
C)nitrogen
D)oxygen

Question 19

Solar energy is the same thing as heat energy.

Question 20

The honey possum (Tarsipes rostratus) is a tiny Australian marsupial that feeds entirely on nectar.Which of the following terms describes the role of a honey possum in its ecosystem?

A)herbivore
B)primary producer
C)primary carnivore
D)secondary carnivore

Question 21

A Viceroy caterpillar feeds on a leaf.One day's feeding consumes 1000 calories worth of leaves.50% of the calories are lost in its feces and 33% of the calories are used in cellular respiration.How many calories of the original intake are available to add to the caterpillar's biomass each day?

A)830 calories
B)670 calories
C)500 calories
D)330 calories
E)170 calories

Question 22

In an ecosystem

A)both energy and nutrients cycle.
B)energy flows and nutrients cycle.
C)energy cycles and nutrients flow.
D)both energy and nutrients flow.

Question 23

According to MacArthur and Wilson's island biogeography theory, which of the following would be expected to have the smallest species richness?

A)the mainland
B)a large island near the mainland
C)a large island far from the mainland
D)a small island near the mainland
E)a small island far from the mainland

Question 24

In an ecosystem, the amount of organic matter produced in a given time that is available for heterotrophs is known as

A)daily yield.
B) gross primary productivity.
C)net primary productivity.
D)effective vitality.

Question 25

The net weight of all of the organisms living in an ecosystem is its

A)productivity.
B)biomass.
C)vital force.
D)photosynthesis minus metabolism.

Question 26

Which one of the following quantities best represents the respiratory heat lost by plants in an ecosystem?

A)gross primary productivity
B)net primary productivity
C)gross primary productivity - net primary productivity
D)gross primary productivity - standing crop biomass

Question 27

In the food chain below, what does the blue jay represent? crabgrass-cricket-garden spider-blue jay-red-tailed hawk

A)herbivore
B)primary producer
C)primary carnivore
D)secondary carnivore

Question 28

During the 1960s, a group of scientists in the northeastern United States conducted an experiment at Hubbard Brook, New Hampshire.A 38-acre watershed was completely deforested and the runoff (water flow) monitored for several years.It was compared to an adjacent watershed that was left untouched.The scientists collected data during those years and found

A)no difference in the amount of runoff from the two areas.
B)an insignificant difference in the amount of nitrogen from the two areas.
C)a tremendous increase in the total amount of runoff from Hubbard Brook although the loss of nitrogen was fairly consistent in both areas.
D)a tremendous increase in the amount of runoff and nitrogen release from Hubbard Brook compared to the control.

Question 29

In a food chain with four trophic levels, what would be the energy in the top trophic level if the energy contained in the primary producer level is 40,000 kcal/m²/yr? Assume a trophic level transfer efficiency of 10%.

A)4,000 kcal/m²/yr
B)400 kcal/m²/yr
C)40 kcal/m²/yr
D)4 kcal/m²/yr

Question 30

Which one of the following ecosystems is most likely to show an inverted biomass pyramid but a normal energy pyramid?

A)grassland
B)open ocean
C)intertidal
D)tropical forest

Question 31

In a food chain consisting of four trophic levels, if the energy present in the top level is 48 kcal/m2/yr, how much energy do you expect in herbivores? (Use an energy transfer rate of 10%.)

A)4.8 kcal/m²/yr
B)48 kcal/m²/yr
C)480 kcal/m2/yr
D)4,800 kcal/m²/yr

Question 32

Which one of the following factors would NOT influence the productivity of an ocean community?

A)the presence of nitrogen-fixing cyanobacteria
B)the season of the year
C)levels of autotrophs
D)fertilizer runoff
E)the amount of rainfall

Question 33

Addition of a primary carnivore to an ecosystem can sometimes influence the whole ecosystem.This process is called

A)ecosystem stabilization.
B)a bottom-up effect.
C)species turnover.
D)disruption.
E)a trophic cascade.

Question 34

A good average value for the amount of energy that reaches the next trophic level is about

A)20%.
B)10%.
C)5%.
D)2%.

Question 35

The following figure shows studies in a stream where enclosures were set up either with trout or with no trout.Which statement is a correct interpretation of the graph about trout, invertebrates, and algae?

A)If trout are present in a system, algae production is low and invertebrate population levels are also low.
B)If trout are present in a system, algae production is high and invertebrate population levels are also high.
C)If trout are present in a system, algae production is high and invertebrate population levels are low.
D)Trout do not seem to affect the algae production; only the invertebrate populations are affected.

Question 36

The rate of production of new biomass by heterotrophs is called

A)secondary productivity.
B)primary productivity.
C)consumer productivity.
D)gross productivity.

Question 37

What feature do the carbon and nitrogen cycles have in common?

A)a large atmospheric component
B)involvement in global climate change
C)often a limiting nutrient
D)mostly local cycling

Question 38

In a marine ecosystem with an inverted biomass pyramid, which trophic level should have the smallest number of organisms?

A)phytoplankton
B)zooplankton
C)primary carnivores (sardines)
D)secondary carnivores (tuna)

Question 39

In the food chain below, what does the garden spider represent? crabgrass-cricket-garden spider-blue jay-red-tailed hawk

A)herbivore
B)primary producer
C)primary carnivore
D)secondary carnivore

Question 40

Energy enters most ecosystems by the process of

A)biosynthesis.
B)respiration.
C)biogeochemical weathering.
D)photosynthesis.

Question 41

In an aquatic ecosystem, a secondary carnivore is temporarily excluded and then, after a period of time, is returned.Which one of the following is NOT an expected top-down effect after it is returned?

A)Primary carnivores become less abundant.
B)Primary productivity increases.
C)Algae decrease.
D)Herbivores become more abundant.

Question 42

The tropics are known to have greater species diversity than the temperate zones.Which explanation for this phenomenon is the LEAST convincing?

A)Seasonal variability is less in the tropics.
B)Niches are narrower in the tropics.
C)Fewer predators in the tropics allow more prey species to flourish.
D)Greater spatial heterogeneity in the tropics creates more niches.