CH 6 review. Name: Class: Date: Completion Complete each sentence or statement.

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Name: Class: Date: ID: A CH 6 review Completion Complete each sentence or statement. Short Answer 1. The of animals was an important event in history for the advancement of agriculture and contributed to a reliable food supply. 2. Because the gases that make up the air can be replaced by natural processes, air is classified as a resource. 3. Sustainable development must be based on principles of ecology as well as. 4. To prevent certain fish populations from collapsing, certain have been temporarily closed. 5. is a hard, bricklike material formed from tropical soils due to deforestation. 6. Microscopic particles, such as dust and ash, that can enter the nose, mouth, and lungs are called. 7. A location that has 170 species of birds has greater than a location that has 100 species of birds. 8. Within each species, genetic diversity refers to the total of all different forms of present in that species. 9. Any species that is threatened with extinction is a(an) species. 10. Excessive levels of DDT in a small algae-eating fish is an example of. 11. Top-level carnivores are at greatest risk from because they have the highest concentration of toxic compounds in their tissues. 12. Zoos have established programs, in which young animals are raised in protected surroundings until the population is stable and are later returned to the wild. 13. Conservation biology integrates information from other scientific disciplines, such as, geography, and natural resource management. 14. The acts as Earth s sunscreen. 15. Intense UV radiation due to ozone depletion can damage plant leaves and tiny in the oceans. 16. What is suburban growth? 17. How do modern subsistence hunters differ from ancient hunter-gatherers? 18. What development in human history led to humans gathering in settlements, towns, and cities? 19. Give an example of how a renewable resource can become limited or nonrenewable. 1

Name: ID: A 20. What is the tragedy of the commons? 21. What are the goals of sustainable development, and upon what principles are sustainable practices based? 22. Contrast biodiversity with species diversity. 23. Why is biodiversity one of Earth s greatest natural resources? 24. Calculate how much DDT could be found in the tissues of a fish on the third trophic level if the concentration of DDT in the water is 10 parts per million. 25. How is hunting a threat to biodiversity? 26. What is a biodiversity hot spot? Where is such a hot spot in the United States? 27. Describe how deforestation might contribute to global warming. 28. What is ozone? Why is it important? 29. Describe three services that are provided by a healthy biosphere. 30. Why are scientists trying to model the possible effects on the atmosphere due to global warming? 2

Name: ID: A Other USING SCIENCE SKILLS Existing Species and Endangered Organisms Table I. How Many Species Are There? Groups of Species Number Identified Possible Total Viruses 5,000 perhaps 500,000 Bacteria 4,000 400,000 to 3 million Fungi 70,000 1 to 1.5 million Protozoans 40,000 100,000 to 200,000 Algae 40,000 200,000 to 10 million Plants 250,000 300,000 to 500,000 Vertebrates 45,000 50,000 Roundworms 15,000 500,000 to 1 million Mollusks 50,000 200,000 Crustaceans 40,000 150,000 Spiders, mites 75,000 750,000 to 1 million Insects 950,000 8 to 100 million Table II. Organisms Listed as Endangered in the United States Type of Organisms Number of Endangered Species Mammals 63 Birds 78 Reptiles 14 Amphibians 10 Fishes 70 Snails 20 Clams 61 Crustaceans 18 Insects 33 Spiders 12 Flowering plants 565 Conifers 2 Ferns and other plants 24 Figure 6 1 31. Calculating According to Figure 6 1, Table I, what is the identified species diversity in the biosphere? 3

Name: ID: A 32. Comparing and Contrasting Which group of species listed in Figure 6 1, Table I, is the most diverse? 33. Using Tables and Graphs Which group of species has the highest number on the list of endangered species in Figure 6 1, Table II? 34. Analyzing Data Which table in Figure 6 1 tells you about the numbers of species whose population size is declining in a way that places it in danger of extinction? 35. Predicting After 10 years, if conservation efforts are supported to protect entire ecosystems, how would Table II in Figure 6 1 likely change? USING SCIENCE SKILLS Figure 6 2 36. Using Charts and Graphs The green revolution has doubled food production over the last 50 years. Starting in 1965, in what year did the amount of chemical fertilizers used worldwide double, according to Figure 6 2? 37. Analyzing Data Describe the data in Figure 6 2. Does it indicate that the green revolution was meeting its goal? Explain. 38. Applying Concepts How might the trend in Figure 6 2 up to 1990 relate to the practice of monoculture? 39. Formulating Hypotheses Formulate a hypothesis that, if supported by testing, would explain the trend shown in Figure 6 2 after 1990. 40. Making Judgments Examine the trend in chemical fertilizer use from 1965 to 1990 shown in Figure 6 2. Is this a sustainable development of resources? Explain. 4

Name: ID: A USING SCIENCE SKILLS Figure 6 3 41. Inferring Evaluate the two graphs in Figure 6 3. Describe what environmental resource these data refer to. Is it a renewable or a nonrenewable resource? 42. Using Tables and Graphs Which two emissions in Graph II of Figure 6 3 contribute most to acid rain? Explain. 43. Making Judgments Examine Graph I of Figure 6 3. From the data given, determine whether the United States can serve as a good example of practicing the principles of sustainable development of a common resource. 44. Comparing and Contrasting Graph I of Figure 6 3 shows that carbon dioxide emissions generally increase in more developed countries. Explain this trend. 45. Analyzing Data Examine both graphs in Figure 6 3. Which two gases that are products of automobile exhaust are produced in the highest amounts? Which one contributes to global warming? Describe the trend in carbon monoxide production. Essay 46. How is Earth like an island? 5

Name: ID: A 47. How can we ensure the sustainable development of water resources? How is water conservation consistent with the principles of sustainable development? 48. Describe the process of desertification. Include a discussion of fertile topsoil and how it changes through soil erosion. 49. What causes acid rain? What is the effect of acid rain on natural habitats? 50. Discuss biodiversity as a source of medicines. Give an example. 51. What are introduced species? How are they a threat to biodiversity? 52. Describe how habitat fragmentation occurs. What is a biological island? How does it differ from large ecosystems? 53. Discuss one of the challenges to conservation efforts in developing countries. Give an example. 54. What is the difference between captive breeding programs and ecosystem preservation in terms of conservation biology? Describe how conservation groups are working to protect biodiversity. 55. Discuss the health effects of damage to the ozone layer and the steps being taken to help deal with the problem. 6

CH 6 review Answer Section COMPLETION 1. ANS: domestication DIF: E REF: p. 141 OBJ: 6.1.1 STO: 3.8.10.B.4 2. ANS: renewable DIF: B REF: p. 144, p. 148 OBJ: 6.2.1 STO: 3.6.12.A.3 3. ANS: economics DIF: B REF: p. 145 OBJ: 6.2.2 STO: 3.6.10.C.7 4. ANS: fisheries DIF: A REF: p. 147 OBJ: 6.2.3 STO: 3.6.10.C.7 5. ANS: Laterite DIF: E REF: p. 146 OBJ: 6.2.3 STO: 3.6.12.A.3 6. ANS: particulates DIF: B REF: p. 148 OBJ: 6.2.3 STO: 3.6.12.A.3 7. ANS: biodiversity DIF: A REF: p. 150 OBJ: 6.3.1 STO: 3.1.12.A.4 8. ANS: genes genetic information DIF: E REF: p. 150 OBJ: 6.3.1 STO: 3.1.12.A.4 9. ANS: endangered DIF: B REF: p. 151 OBJ: 6.3.2 STO: 3.1.12.A.4 10. ANS: biological magnification DIF: A REF: p. 152 OBJ: 6.3.2 STO: 3.1.12.A.1 11. ANS: biological magnification DIF: E REF: p. 152 OBJ: 6.3.2 STO: 3.1.12.A.1 12. ANS: captive breeding DIF: A REF: p. 154 OBJ: 6.3.3 STO: 3.8.10.C.3 1

13. ANS: genetics DIF: E REF: p. 154 OBJ: 6.3.3 STO: 3.8.10.C.3 14. ANS: ozone layer DIF: B REF: p. 157 OBJ: 6.4.1 STO: 3.6.12.A.3 15. ANS: phytoplankton DIF: A REF: p. 157 OBJ: 6.4.1 STO: 3.1.12.A.1 SHORT ANSWER 16. ANS: Suburban growth is a pattern of growth that occurs when cities become crowded and people move to the suburbs. DIF: B REF: p. 143 OBJ: 6.1.1 STO: 3.6.10.C.9 17. ANS: Nearly all modern subsistence hunters use some form of technology, such as guns, snowmobiles, or manufactured tools. DIF: A REF: p. 140 OBJ: 6.1.1 STO: 3.8.10.C.1 18. ANS: The spread of agriculture and a dependable supply of food enabled humans to remain in one place and live together in larger settlements. DIF: B REF: p. 141 OBJ: 6.1.1 STO: 3.8.10.B.4 19. ANS: A single tree in a forest is renewable, but a whole population of trees is nonrenewable because of permanent changes that would happen to ecosystems if they were lost. DIF: E REF: p. 144 OBJ: 6.2.1 STO: 3.6.12.A.3 20. ANS: Resources common to everyone, such as air or parts of the oceans, may eventually be destroyed because no one is responsible for preserving them. DIF: A REF: p. 144 OBJ: 6.2.1 STO: 3.6.12.A.3 21. ANS: Sustainable-development practices are aimed at using natural resources at a rate that does not deplete them. Sustainable practices are based on principles of ecology and economics. DIF: A REF: p. 145 OBJ: 6.2.3 STO: 3.6.10.C.7, 3.8.10.C.3 2

22. ANS: Biodiversity is the sum total of the genetically based variety of all organisms in the biosphere. Species diversity refers to the number of species in the biosphere. DIF: E REF: p. 150 OBJ: 6.3.1 STO: 3.1.12.A.4 23. ANS: Species of many kinds provide us with food, industrial products, and medicines. DIF: B REF: p. 150 OBJ: 6.3.1 STO: 3.1.12.A.4 24. ANS: 10 (water) 10 (producers) 10 (herbivores) 10 (fish) = 10,000 parts per million DIF: E REF: p. 72, p. 152 OBJ: 6.3.2 STO: 3.1.10.D.1 25. ANS: Animals, such as the carrier pigeon, have often been hunted to extinction. Populations of rare animals are hunted for fur, hides, meat, and other body parts, such as horns, which makes them vulnerable to extinction. DIF: B REF: p. 151 OBJ: 6.3.2 STO: 3.1.12.A.4 26. ANS: A biodiversity hot spot is a place where significant numbers of habitats and species are in immediate danger of extinction as a result of human activity. The California Floristic Province is a hot spot in the United States. DIF: A REF: p. 155, p. 156 OBJ: 6.3.3 STO: 3.1.12.A.4 27. ANS: Deforestation, especially when accomplished by burning, removes plants that use carbon dioxide in photosynthesis. Burning trees produces carbon dioxide, which leads to global warming. DIF: E REF: p. 159 OBJ: 6.4.1 STO: 3.6.12.A.3 28. ANS: Ozone is a gas made of molecules containing three oxygen atoms that, in the upper atmosphere, absorbs harmful UV radiation. DIF: B REF: p. 157 OBJ: 6.4.1 STO: 3.6.12.A.3 29. ANS: Possible answers include: solar energy, production of oxygen, temperature control, air and water purification, food production, habitats for wildlife, storage and recycling of nutrients, and other services listed in Figure 6 22 of the text. DIF: A REF: p. 160 OBJ: 6.4.1 STO: 3.6.12.A.3 30. ANS: Models of enormous phenomena such as global warming help scientists make predictions. Global warming affects ecosystems and the geographic distribution of species. DIF: E REF: p. 159 OBJ: 6.4.1 STO: 3.1.10.B.2 3

OTHER 31. ANS: Students should total all the numbers in the column labeled Number Identified to obtain 1,584,000 species. DIF: B REF: p. 150 OBJ: 6.3.1 STO: 3.6.12.B.4 32. ANS: The most diverse group of species is insects, with 950,000 identified species. DIF: B REF: p. 150 OBJ: 6.3.1 STO: 3.6.12.B.4 33. ANS: The group flowering plants has the highest number of species on the list, with 565 endangered species. DIF: B REF: p. 151 OBJ: 6.3.2 STO: 3.6.12.B.4 34. ANS: Table II DIF: B REF: p. 151 OBJ: 6.3.2 STO: 3.6.12.B.4 35. ANS: The list will likely have a lower number of endangered species. DIF: B REF: p. 154 OBJ: 6.3.3 STO: 3.6.12.B.4 36. ANS: 1980 DIF: A REF: p. 142 OBJ: 6.1.1 STO: 3.6.12.B.4 37. ANS: The use of chemical fertilizers increased steadily from the beginning of the green revolution until 1990. During those years, the global food production nearly doubled, which was the goal of the green revolution. Other circumstances, however, caused fertilizer use to decrease after 1990. DIF: A REF: p. 142 OBJ: 6.1.1 STO: 3.6.12.B.4 38. ANS: One strategy of the green revolution was to use a method called monoculture, in which farmers planted large fields with a single, highly productive crop year after year. To support these fields, farmers relied on chemical fertilizers to boost plant growth. DIF: A REF: p. 141 OBJ: 6.1.1 STO: 3.6.12.B.4 4

39. ANS: Possible answers include: Increased awareness of the damage being done to the biosphere reduced the use of chemical fertilizers. The development of better land-use techniques, such as contour plowing and alternating crops, led to a reduced dependence on chemical fertilizers. DIF: A REF: p. 142, p. 145 OBJ: 6.2.3 STO: 3.6.12.B.4 40. ANS: The kind of increase in the use of chemical fertilizers from 1965 to 1990 is not sustainable. The application of fertilizers can interfere with food webs and biogeochemical cycles. DIF: A REF: p. 145 OBJ: 6.2.2 STO: 3.6.12.B.4 41. ANS: The graphs both refer to carbon dioxide and other air pollutants. The air we breathe is a renewable resource because it is replenished by natural processes. DIF: E REF: p. 144, p. 148 OBJ: 6.2.1 STO: 3.6.12.B.4 42. ANS: Sulfur dioxide and nitrogen oxides are listed on Graph II. When gases containing nitrogen and sulfur compounds combine with water vapor in the air, they form drops of nitric and sulfuric acids. These strong acids can drift for miles before they fall as acid rain. DIF: E REF: p. 148 OBJ: 6.2.3 STO: 3.6.12.B.4 43. ANS: The United States produced more carbon dioxide per person than any other listed country. Students may not think this is a good example of sustainable development of a common resource. DIF: E REF: p. 145 OBJ: 6.2.2 STO: 3.6.12.B.4 44. ANS: More developed countries are more industrialized, and many industries rely on fossil fuel. The burning of fossil fuels produces carbon dioxide. DIF: E REF: p. 159 OBJ: 6.4.1 STO: 3.6.12.B.4 45. ANS: Graph I indicates a high production of carbon dioxide. Graph II shows a high level of carbon monoxide. Carbon dioxide is a greenhouse gas and contributes to global warming. Carbon monoxide production was lower in 1998 than in 1970, indicating a trend toward lower levels. DIF: E REF: p. 159 OBJ: 6.4.1 STO: 3.6.12.B.4 5

ESSAY 46. ANS: Earth is like an island in space. All the living things on Earth share a limited resource base. We all depend on the natural ecological processes that sustain these resources. The human population is still growing, but the planet we live on is not. Along with this growing population come increasing demands on Earth s air, water, land, resources, and living things. DIF: A REF: p. 139 OBJ: 6.1.1 STO: 3.6.12.A.3 47. ANS: The sustainable development of water resources involves protection of the natural systems involved in the water cycle. For example, wetlands such as swamps help to purify the water running through them. As water flows slowly through a swamp, densely growing plants filter certain pollutants out of the water. Similarly, forests and other vegetation help to purify the water that seeps into the ground or runs off into rivers and lakes. Water conservation is an important aspect of sustainable development because the demand for water is growing rapidly in many parts of the United States. For example, agriculture uses more than three quarters of the water consumed in this country. Measures such as drip irrigation reduce water lost to evaporation and are consistent with the principles of sustainable development in the application of appropriate technology. DIF: E REF: p. 145, p. 149 OBJ: 6.2.2 STO: 3.6.10.C.7, 3.8.10.C.3 48. ANS: Fertile topsoil is a mixture of humus, sand, clay, and rock particles. Most of the humus that makes soil fertile is in the uppermost layer of the soil, called topsoil. Such soil is produced by long-term interactions between the soil and plants growing in it. Deep roots of long-lived grasses hold soil in place against rain and wind. Plowing land removes the roots that hold the soil in place. This increases the rate of soil erosion the wearing away of surface soil by water and wind. In certain parts of the world with dry climates, a combination of farming, overgrazing, and drought has turned once productive areas into deserts a process called desertification. DIF: E REF: p. 145 OBJ: 6.2.3 STO: 3.8.10.A.1 49. ANS: Many combustion processes, such as the burning of fossil fuels, release acidic gases containing nitrogen and sulfur compounds into the air. When these gases combine with water vapor, they form drops of nitric and sulfuric acids. These drops then fall as acid rain. Acid rain can kill plants by damaging their leaves and changing the chemistry of soils and standing-water ecosystems. Acid rain may also dissolve and release toxic elements, such as mercury, from the soil, allowing them to enter other portions of the biosphere. DIF: A REF: p. 148 OBJ: 6.2.3 STO: 3.6.12.A.3 6

50. ANS: Biodiversity is one of Earth s greatest natural resources. Species of many kinds have provided us with foods, industrial products, and medicines including painkillers, antibiotics, heart drugs, antidepressants, and anticancer drugs. For example, the rosy periwinkle plant is the source of substances used to treat certain cancers. When biodiversity is lost, potential sources of material with significant value to the biosphere and to humankind may be lost with it. DIF: A REF: p. 150 OBJ: 6.3.1 STO: 3.1.12.A.4 51. ANS: One of the most important threats to biodiversity today comes from apparently harmless plants and animals that humans transport around the world either accidentally or intentionally. Introduced into new habitats, these organisms often become invasive species that reproduce rapidly and crowd out native species. Invasive species increase their populations rapidly because their new habitat lacks the parasites and predators that control their populations in their native environments. DIF: A REF: p. 153 OBJ: 6.3.2 STO: 3.1.12.A.4 52. ANS: When land is developed, natural habitats may be destroyed. Development often splits ecosystems into pieces, a process called habitat fragmentation. Fragmentation transforms remaining pieces of habitat into biological islands. Habitat islands are very different from large, continuous ecosystems. The smaller the island, the fewer species can live there, the smaller the populations can be, and the more vulnerable they are to further disturbance or climate change. As habitats disappear, the species that live in those habitats vanish. DIF: E REF: p. 151 OBJ: 6.3.2 STO: 3.8.10.A.1 53. ANS: Sometimes, the need to protect biodiversity is greatest in countries that are least able to do so. The destruction of tropical rain forests, for example, is the single greatest threat to biodiversity on land. Most rain forests are located in developing countries, where conservation goals must be weighed against the survival needs of the human population. DIF: A REF: p. 155 OBJ: 6.3.3 STO: 3.8.10.C.2, 3.8.10.A.1 54. ANS: Some zoos have established captive breeding programs, in which young animals are raised in protected surroundings until the population is stable and are later returned to the wild. Today, conservation efforts focus on protecting entire ecosystems as well as single species. Protecting an ecosystem will ensure that the natural habitats and the interactions of many different species are preserved at the same time. Governments and conservation groups worldwide are working to set aside land or expand existing areas as parks and reserves. Marine sanctuaries are being designated to protect marine resources, such as coral reefs and marine mammals. Ecologists are realizing, however, that even these areas may not be enough to conserve the world s biodiversity. DIF: E REF: p. 154, p. 155 OBJ: 6.3.3 STO: 3.8.10.C.3 7

55. ANS: Damage to the ozone layer by chlorofluorocarbons (CFCs) has left a vast area over each of the polar regions that is thin enough to allow higher than normal amounts of UV radiation to strike the Earth. UV radiation causes sunburn, and excess exposure to UV can cause cancer, damage eyes, and decrease organisms resistance to disease. Intense UV can damage tissue in plant leaves and phytoplankton. The United States and many other nations have an international agreement to phase out the use of CFCs. DIF: E REF: p. 157, p. 158 OBJ: 6.4.1 STO: 3.8.10.C.4 8