Record your exam number on your scantron: ______

Record your exam number on your scantron: ______

Unit 3 Exam

Mark the best answer to each question on your scantron.

1.We are usually referring to species diversity when we talk about biodiversity. However, genetic diversity is also important to ecological systems because diverse genes

A)increase the efficiency and productivity of a system because all niches are filled.

B)allow an individual organism to adapt to its changing environment.

C)are necessary for a population to evolve in a changing environment.

D)lead to diverse ecological processes in a biological community.

E)are key to balance an ecosystem.

2.Ecological diversity is a measure of the number of

A)different species in an ecosystem.

B)niches, trophic levels, and ecological processes of a biological community.

C)different versions of the same gene in an ecological community.

D)different kinds of organisms within a community or ecosystem.

E)sizes, colors, and shapes of organisms within an ecological community.

Use the following scenario to answer four questions 3-4. Your friend is upset because his conception of what a species is has been challenged. His professor told him that there are some problems associated with the common way that a species is identified. Your friend learned what a species was while in high school and it was reinforced during his first year of college. He also refers to the chapter 13 in your environmental science book for this definition. Your friend wonders if this professor knows what she is talking about. You explain to him that there really are some problems associated with the common way that a species is defined and you think that this professor is correct.

3.The common way that a species is defined in biology (the way it is defined in Chapter 13) is that a species includes all organisms that are similar enough to

A)fill the same niche.

B)live together.

C)look alike.

D)produce fertile offspring in nature.

E)occupy the same community.

4.The underlying assumption with the common definition of a species is that _______________________ prevents groups of similar organisms from exchanging genes.

A)reproductive isolation caused by intraspecific competition

B)reproductive isolation caused by interspecific competition

C)genetic diversity

D)ecological diversity

E)reproductive isolation caused by geography, physiology, or behavior

5.The total number of living species is probably

A)between 3 million and 50 million.

B)at least 300 million.

C)between 75 and 95 million.

D)between 500,000 and 1 million.

E)about 450,000.

6.Approximately how many species have been identified on Earth?

A)A little more than 3 million

B)About 30 million

C)A little less than 1 million

D)A little less than 1.5 million

E)About 500,000

7.Most of the species that are yet undiscovered are probably

A)multicellular plants

B)mammals and reptiles.

C)birds and fish.

D)invertebrates and vertebrates.

E)invertebrates, bacteria, and fungi.

8.One of the reasons humans rely heavily on only a few food crops is because

A)there are few edible wild species.

B)it would be difficult for small farmers to cultivate the fragile wild species.

C)we have not explored the cultivation of thousands of edible wild species.

D)we have already focused on the best tasting species for domestication and cultivation.

E)All of these factors contribute to a heavy reliance on only a few species.

9.Which of the following is not a benefit of biodiversity for humans?

A)food

B)drugs and medicines

C)ecological services

D)aesthetics

E)All of these are benefits of biodiversity.

10.Which of the following drugs is not derived from a naturally occurring organism?

A)morphine

B)cortisone

C)penicillin

D)aspirin

E)All of these are natural products.

11.The pharmaceutical industry has an interest in preventing species extinction because

A)it wants to increase diversity in North America.

B)people are healthier in a healthy environment.

C)undiscovered species may provide important new drugs.

D)they see the benefits of eco-design.

E)most taxonomists are drug makers.

12.Soil formation and water purification are examples of _________ based on the biodiversity that benefit humans.

A)health benefits

B)availability of food

C)ecological services

D)geological cycles

E)aesthetic benefits

13.Which of the following is or would be an example of a natural cause of extinction?

A)The passenger pigeon that went extinct at the beginning of this century.

B)An insect species in the tropical forest that cannot escape predation by native bird species in the forest.

C)Genetic assimilation as in the case of the hybridization of gray wolves or black ducks with mallards.

D)Cutting and burning of trees to stop the infestation of the Asian long-horned beetle.

E)All of these are examples of a natural cause of extinction.

14.Habitat fragmentation usually leads to a(n)

A)increase in the number of introduced species.

B)increase in biodiversity due to the isolated populations.

C)more stable environment.

D)reduction in the number of introduced species.

E)decrease in biodiversity.

15.The current rate at which species are becoming extinct is estimated to be

A)80% of all species per decade.

B)100's to 1000's of species per decade.

C)1 species per decade.

D)2 to 3 species per decade.

E)50 species per decade.

16.Extinction is the term used when all members of a species

A)are in danger of disappearing in a locality.

B)disappear in a locality.

C)are threatened with imminent habitat loss.

D)die.

E)live in zoos.

17.The main reason for the current high rate of animal extinctions is

A)habitat destruction worldwide.

B)uncontrolled sport hunting in the developed world.

C)commercial harvesting of wildlife in Africa.

D)drought conditions caused by the greenhouse effect.

E)poaching of exotic species for sale and trade.

18.The drastic reduction in rhinoceros is due mostly to

A)over harvesting for their meat and hide.

B)introduction of exotic species that compete for their food.

C)habitat destruction.

D)the supposed medicinal value of their horns.

E)All of these have contributed equally to the decrease in the rhinoceros population.

19.What did CITES (the Convention on International Trade in Endangered Species) do in 1989 to help save the African elephant population?

A)wrote laws making it illegal to kill or transport elephants

B)banned all trade in ivory

C)established parks

D)provided funds to hire park rangers to prevent poaching.

E)established breeding programs

20.The main reason for continued trade in endangered species is

A)ruthless traders and collectors in tropical countries.

B)pet lovers and collectors who like exotic species.

C)the presence of poachers in tropical countries.

D)the need for international capital exchange in developing countries.

E)a surplus of these species in their home countries.

21.Which of the following statements about trade in endangered species is false?

A)The principal exporters of endangered species are developing countries.

B)The principal importers of endangered species are developed countries.

C)Over harvesting affects animals more than plants.

D)People who enjoy collecting exotic plants and animals are the main contributors to the trade.

E)None of these statements are false.

22.Animal control efforts kill some 700,000 birds and animals per year. Which of the following is not an argument of the critics of the animal control program in the United States?

A)It kills nontarget species.

B)Animal control programs need to focus more on the higher trophic level species (top consumers) rather than the lower trophic species (herbivores).

C)It is expensive to taxpayers.

D)Other controls are more effective and more humane.

E)All of these are arguments of critics of the animal control program.

23.Exotic is another word for

A)beautiful.

B)tropical.

C)desirable.

D)rare.

E)foreign.

24.Introduced (exotic) species tend to __________ the balance of ecosystems and ______ biodiversity.

A)upset, decrease

B)maintain, enhance

C)increase, decrease

D)upset, increase

E)increase, enhance

25.The zebra mussel was introduced to the Great Lakes

A)from the Mississippi River.

B)intentionally by professional anglers.

C)accidentally in ocean-going ship ballast.

D)intentionally by recreational anglers.

E)as a food source.

26.Which of the following would be a characteristic of an exotic plant species?

A)Has many predators and diseases.

B)Is a secondary consumer (trophic levels).

C)Produces a few seeds after many years to reach maturity.

D)Is a specialist, for example, has a low range of tolerance for soil acidity.

E)Is an opportunist that is desired by humans for food or ornamental value.

27.Introduced exotic organisms are especially dangerous to new environments because they destroy the native biodiversity. This happens because they

A)do not have natural predators.

B)are freed of parasites that kept them in check in their native home.

C)are freed of pathogens that kept them in check in their native home.

D)are freed of competition that kept them in check in their native home.

E)All of the above describe why exotic organisms are dangerous to native biodiversity.

28.Genetic assimilation occurs when a rare species

A)is subject to selection pressures and undergoes a change in genetic material.

B)disappears through crossbreeding with a related species.

C)is strengthened through crossbreeding.

D)mutates to adapt to environmental conditions.

E)is so similar that genetic diversity is lost.

29.A species in imminent danger of extinction is classified by the US Endangered Species Act as

A)valuable.

B)vulnerable.

C)at risk.

D)threatened.

E)endangered.

30.A species that is naturally rare or that has been depleted to dangerous levels is known, according to the Endangered Species Act, as a(n) ________ species.

A)vulnerable

B)endangered

C)threatened

D)at risk

E)unusual

31.A threatened species may be extinct or near extinction

A)in the near future.

B)in most of their natural range.

C)only in the distant future.

D)already.

E)never.

32.The main reason that there are relatively few invertebrates categorized as endangered species is because

A)they do not have a significant contribution to ecosystems.

B)invertebrates are more numerous and the relative percentages are similar.

C)we consider other groups, such as mammals, to be more interesting and desirable.

D)worldwide there are relatively few invertebrates when compared to plants.

E)Since there are 532 invertebrates considered endangered, none of the above is true.

33.Canada has fewer listed endangered species than the United States because

A)Canada does not have a way to identify endangered species.

B)much of Canada lies in the far north, where diversity is low.

C)Canadians are more careful with wildlife.

D)there are fewer people in Canada when compared to the United States.

E)the United States has more wild areas.

34.In general, funding for recovery programs is given to species that are

A)most numerous.

B)in the most danger.

C)the most important.

D)keystone species.

E)most well known.

35.The objective of a species recovery plan is to

A)interbreed threatened species with common species.

B)increase an endangered species population until it is no longer endangered.

C)invest corporate capital in species maintenance.

D)study the species for a better understanding of its role in the biological community.

E)protect the species to aid other organisms and resources in the ecosystem.

36.Under habitat conservation plans, developers are allowed to destroy habitats or even "take" endangered organisms by

A)funding conservation research.

B)removing predators and competitors.

C)taking steps that benefit other endangered species.

D)improving habitat other areas.

E)All of the above allow developers to destroy habitats and take endangered organisms.

37.Island biogeography explains the phenomenon of _______ terrestrial species on islands small and far from the mainland when compared to larger islands that are closer to the mainland and have __________ terrestrial species.

A)larger, smaller

B)fewer, more

C)smaller, larger

D)about the same, about the same

E)more, fewer

38.Conservationists and wildlife managers use gap analysis to

A)find unprotected landscapes that are rich in species.

B)establish connecting corridors.

C)predict the next evolutionary change an organism will undergo.

D)bring different managing agencies into closer accord.

E)isolate and contain populations.

39.How is diversity lost in small populations?

A)A flounder effect occurs when a few individuals establish a new population.

B)A demographic bottleneck arises when only a few individuals survive some catastrophe..

C)Genetic Drift occurs and there is a reduction in a populations gene frequency.

D)Inbreeding occurs because of lack of diverse genes.

E)All of the above describe how diversity is lost in small population.

40.In general, an animal whose population is widely scattered geographically is _______ as/than one whose population is geographically restricted.

A)less likely to become extinct

B)equally likely to become extinct

C)less unlikely to become extinct

D)more likely to become extinct

E)equally unlikely to become extinct

Name _______________________________

Hour _____

Score _______/20

Unit 3 Free-Response

Read the following passage and answer the questions below. Answer all parts of the questions to receive full credit.

The American whooping crane and the California condor are two of North Americas largest birds. Although both are rare and endangered, they are protected, and large preserves are available for them. The two species, however, seem to be responding differently to these conservation efforts.

In 1973, the whooping crane population was reduced to 14 individuals. It has since recovered; currently more than 200 birds live and breed in the wild. In the preservation of endangered species, the whooping crane is a success story. On the other hand, the California condor population declined rapidly so that no bird remained in the wild between 1987 and 1992. Condors were reintroduced into the wild after 1992 and approximately 50 condors currently live in the wild in California and Arizona. However, the recovery program cannot yet be considered a success.

(a) Identify and describe TWO possible causes for the decline of these species. (Describe one cause for each species.) (6 points)

(b) Describe TWO measures that were taken to protect these species. (Describe one measurement for each species. Specify which of the species benefited from each measure.) (4 Points)

(c) Describe TWO important characteristics of an endangered species that would cause it to be slow to recover. (4 Points)

Identify and Describe 3 benefits to maintaining the biodiversity of an ecosystem. (6 points)

Unit 3 Odd Grasshopper Answer Key1.C

2.B

3.D

4.E

5.A

6.D

7.E

8.C

9.E

10.E

11.C

12.C

13.B

14.E

15.B

16.D

17.A

18.D

19.B

20.B

21.C

22.B

23.E

24.A

25.C

26.E

27.E

28.B

29.E

30.B

31.A

32.A

33.C

34.B

35.E

36.B

37.E

38.C

39.E

40. A

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