Deck 20: Communities and Ecosystems

Question 1

What is one way in which energy flow differs from chemical cycling?

A) Energy flow is unidirectional; chemical elements can be recycled.
B) Energy can enter but cannot leave an ecosystem; chemical elements can leave but cannot enter an ecosystem.
C) Energy flows from lower to higher trophic levels; chemicals cycle from higher to lower trophic levels.
D) Energy can both enter and leave an ecosystem; chemical elements always remain within a single ecosystem.

Answer 1

A

Question 2

As a result of a severe disturbance,a community will ______.

A) not be repopulated
B) be replaced by a community that is completely different from the previous community
C) not recover for thousands of years
D) undergo succession

Answer 2

D

Question 3

The present rate of species loss ______.

A) suggests that about 25% of all plant and animal species may be extinct by the end of the century
B) is about the same as it has been during the last 100,000 years
C) is as much as 100 times higher than at any time in the last 100,000 years
D) is slower than in recent years because of conservation efforts

Answer 3

C

Question 4

Organisms that consume producers are ______.

A) detritivores
B) decomposers
C) primary consumers
D) producers

Question 5

In the food chain grass → antelope → human → lion,the antelope is

A) both an herbivore and a secondary consumer.
B) both a producer and a primary consumer.
C) both an herbivore and a primary consumer.
D) a secondary consumer only.

Question 6

On average,what percentage of the energy in one trophic level becomes incorporated into the next higher trophic level?

A) 10%
B) 30%
C) 50%
D) 90%

Question 7

Several years ago I was crossing the border from Canada to the United States and I had a bag of Washington State apples with me. The customs officer at the border would not let me take the apples with me into the United States (and I really hated the idea of getting rid of a bag of perfectly good apples). Why did the customs officer refuse to allow me to cross the border with my apples?

A) Washington State apples are considered an endangered fruit.
B) Apples grown in the United States for export may be contaminated with DDT.
C) There may have been a species that was not native to the United States hitching a ride on my apples.
D) Economics: If I couldn't bring the apples in with me, I would have to buy my apples from a store in the United States.

Question 8

Approximately what percentage of the visible light that reaches Earth's producers is converted to chemical energy?

A) 10%
B) 0.1%
C) 1%
D) 0.01%

Question 9

Most decomposers are _____.

A) plants and fungi
B) bacteria and plants
C) fungi and prokaryotes
D) animals

Question 10

Biomass is the total amount of ______ an ecosystem.

A) organic matter tied up in the consumers of
B) organic matter tied up in the producers of
C) chemical elements recycled by the detritivores of
D) living organic material in

Question 11

The single greatest threat to biodiversity comes from ______.

A) habitat destruction and fragmentation
B) invasive species
C) overexploitation
D) pollution

Question 12

Bears eat berries,humans,and large fish; large fish eat smaller fish and insects; humans eat bears,large fish,and berries; Venus flytraps eat insects.The scenario described here is an example of ______.

A) an ecosystem
B) parasitism
C) a food web
D) a food chain

Question 13

In the food chain grass → antelope → human → lion,the human is a(n)______.

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

Question 14

An example of a mutualism,or +/+ relationship,is ______.

A) the relationship between corals and unicellular algae
B) cryptic coloration in frogs
C) herbivory
D) the relationship between Virginia's warblers and orange-crowned warblers, which use some of the same resources

Question 15

Populations of two coexisting species are both tertiary consumers in a community. What relationship may exist between these two organisms?

A) predation
B) mutualism
C) competition
D) commensalism

Question 16

Small fishes that eat zooplankton are

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

Question 17

In order to assess the species diversity of a community,you would need to know the number of different species present as well as ______.

A) the number of trophic levels in the community
B) the intensity of interspecific competition in the community
C) the fraction of these species that are plants
D) the relative abundance of the different species

Question 18

Herbivory is an example of a _____ interaction.

A) +/+
B) -/-
C) 0/+
D) +/-

Question 19

The rate at which an ecosystem's producers convert solar energy to chemical energy stored in biomass is called ______.

A) energy flow
B) chemical cycle
C) primary productivity
D) trophic structure

Question 20

Which of these convert organic matter to inorganic matter by breaking down dead organisms?

A) producers
B) detritivores
C) decomposers
D) primary consumers

Question 21

Movement corridors are ______.

A) always created by humans
B) only found along stream sides
C) beneficial because they allow for dispersal, but not harmful
D) harmful because they allow for the spread of disease and beneficial because they allow for dispersal

Question 22

Species found in only one place on Earth are called ______ species.

A) hot spot
B) exotic
C) keystone
D) endemic

Question 23

Modern conservation science increasingly aims at ______.

A) protection of federally listed endangered species
B) countering pollution
C) sustaining entire ecosystems
D) maintenance of genetic diversity within species

Question 24

Sustainable development ______.

A) will require making difficult decisions regarding the environment and lifestyle
B) must be achieved if the human species is to survive
C) will require global, multinational cooperation
D) involves all of the above

Question 25

Which of these organisms convert atmospheric nitrogen gas to a form that can be utilized by plants?

A) bacteria
B) protists
C) animals
D) fungi

Question 26

The primary goal of conservation biology is to ______.

A) catalog species
B) maximize the land set aside for wildlife
C) integrate human culture back into nature
D) counter the loss of biodiversity

Question 27

The major abiotic reservoir for phosphorus is ______.

A) the oceans
B) the atmosphere
C) rock
D) dead organic matter

Question 28

A movement corridor ______.

A) is a path used by migratory animals when they move to their winter habitats
B) is the path most commonly used by an animal within its home range
C) connects otherwise isolated patches of quality habitat for a species
D) is a natural component of the environment

Question 29

Which type of ecosystem has low production but nonetheless contributes a large proportion of Earth's total net primary production?

A) tropical rain forest
B) coral reef
C) open ocean
D) desert

Question 30

Please refer to the following art to answer the following question(s).

Refer to the figure above. This photo represents ______ community(ies).

A) 0
B) 1
C) 2
D) You cannot tell from the photo.

Question 31

Why are most food chains limited to three to five trophic levels?

A) The higher the trophic level, the larger the organism; the larger the organism, the less likely it will be prey.
B) The nutritional quality of existing biomass decreases with increasing trophic level.
C) Most ecosystems have insufficient space to support the increased number of organisms that more trophic levels would require.
D) There is insufficient energy to support more trophic levels.

Question 32

E.O.Wilson coined the term ______ for our innate appreciation of wild environments and living organisms.

A) bioremediation
B) bioethics
C) biophilia
D) biophobia

Question 33

With regard to nutrient pollution in aquatic ecosystems,when is the worst time to apply fertilizer to your lawn?

A) when it is raining, or is about to rain
B) when it is cold, or is about to get cold
C) at the same time you apply pesticides
D) at night

Question 34

The atmosphere is approximately 80% ______ gas.

A) CO₂
B) H₂O
C) CH₄
D) N₂

Question 35

Landscape ecology ______.

A) is the application of ecological principles to the study of land-use patterns
B) focuses primarily on how to restore human-altered ecological systems
C) deals primarily with ecosystems in urban settings
D) deals with the study of the ranges of different species

Question 36

Small areas that have a large number of endangered and threatened species are referred to as ______.

A) biologically magnified
B) endemic environments
C) biodiverse environments
D) biodiversity hot spots

Question 37

______ convert nitrogen from a form that can be assimilated by plants to N₂.

A) Nitrifying bacteria
B) Nitrogen-fixing bacteria living in the soil
C) Denitrifying bacteria
D) Nitrogen-fixing bacteria living in the root nodules of legumes

Question 38

A regional assemblage of interacting ecosystems is a ______.

A) biome
B) landscape
C) movement corridor
D) hot spot

Question 39

Besides the atmosphere,abiotic reservoirs of carbon dioxide include

A) fossil fuels and dissolved carbon compounds in the oceans.
B) rocks and dissolved carbon compounds in the oceans.
C) fossil fuels only.
D) rocks only.

Question 40

Plants can utilize the ______ form of nitrogen.

A) thiol
B) N₂
C) amino
D) nitrate

Question 41

Use the following information to answer the following question(s).
Malaria is an infectious disease caused by a unicellular eukaryotic organism belonging to the genus Plasmodium. These eukaryotic organisms are transmitted from one person to another by the female Anopheles mosquito when it feeds on human blood. Within humans, the Plasmodium spp. destroy red blood cells and, without effective treatment, serious infections can lead to death. Currently, more than 400 million people are afflicted with malaria and between 1 to 3 million people die from it each year. Historically, a chemical compound called quinine has been used in developing effective drugs against malaria. In its natural environment, quinine is produced by certain trees native to South America. This chemical is synthesized in the outer layer of tree trunks and acts as an herbivore deterrent.
Based on the relationship between Plasmodium spp.and humans,these organisms would be considered ______.

A) parasites
B) hosts
C) producers
D) carnivores

Question 42

Use the following information to answer the following question(s).
Malaria is an infectious disease caused by a unicellular eukaryotic organism belonging to the genus Plasmodium. These eukaryotic organisms are transmitted from one person to another by the female Anopheles mosquito when it feeds on human blood. Within humans, the Plasmodium spp. destroy red blood cells and, without effective treatment, serious infections can lead to death. Currently, more than 400 million people are afflicted with malaria and between 1 to 3 million people die from it each year. Historically, a chemical compound called quinine has been used in developing effective drugs against malaria. In its natural environment, quinine is produced by certain trees native to South America. This chemical is synthesized in the outer layer of tree trunks and acts as an herbivore deterrent.
Humans,mosquitoes,and Plasmodium together would be considered a(n)______.

A) population
B) community
C) ecosystem
D) population and community

Question 43

Please refer to the following art to answer the following question(s).

Refer to the following figure. If there were an additional trophic level that consisted of organisms that prey on snakes,about how much energy would be available to organisms at that trophic level?

A) 100 kcal
B) 90%
C) 1 kcal
D) 10 kcal

Question 44

Please refer to the following art to answer the following question(s).

The figure below shows the growth curves of two populations of Paramecium,P.aurelia and P.caudatum.From the data,we can conclude that ______.

A) the ecological niches of the two species are very different
B) P. aurelia is a predator of P. caudatum
C) P. aurelia and P. caudatum have a mutualistic relationship
D) P. aurelia is the superior competitor in this habitat

Question 45

Use the following information to answer the following question(s).
Malaria is an infectious disease caused by a unicellular eukaryotic organism belonging to the genus Plasmodium. These eukaryotic organisms are transmitted from one person to another by the female Anopheles mosquito when it feeds on human blood. Within humans, the Plasmodium spp. destroy red blood cells and, without effective treatment, serious infections can lead to death. Currently, more than 400 million people are afflicted with malaria and between 1 to 3 million people die from it each year. Historically, a chemical compound called quinine has been used in developing effective drugs against malaria. In its natural environment, quinine is produced by certain trees native to South America. This chemical is synthesized in the outer layer of tree trunks and acts as an herbivore deterrent.
Despite being used for many years,quinine-based drugs have not led to the eradication of malaria and currently there are mosquitoes that are resistant to the compound. Which of the following were likely important in the development of this resistance to quinine?

A) natural selection
B) mutualism
C) interspecific competition
D) biological magnification

Question 46

Please refer to the following art to answer the following question(s).

In the ecosystem shown above,a toxin that accumulates in body tissues would have the largest effect on ______.

A) corals that obtain their food from photosynthesizing dinoflagellates
B) herbivorous shrimp
C) fish that eat shrimp and other invertebrates
D) The toxin would affect all of these equally.