How to Use This Presentation

1. How to Use This Presentation How to Use This Presentation • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. • You may exit the slide show at any time by pressing the Esc key. • To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” • To advance through the presentation, click the right-arrow key or the space bar. • From the resources slide, click on any resource to see a presentation for that resource. • From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. • You may exit the slide show at any time by pressing the Esc key.

2. Resources Bellringers Chapter Presentation Transparencies Standardized Test Prep Image and Math Focus Bank CNN Videos Visual Concepts

3. Chapter 21 Environmental Problems and Solutions Table of Contents Section 1 Environmental Problems Section 2 Environmental Solutions

4. Chapter 21 Section1 Environmental Problems Bellringer • What is the difference between a renewable resource and a nonrenewable resource? • Write your answers in your science journal.

5. Chapter 21 Section1 Environmental Problems Objectives • List five kinds of pollutants. • Distinguishbetween renewable and nonrenewable resources. • Describe the impact of exotic species.

6. Chapter 21 Section1 Environmental Problems Objectives, continued • Explain why human population growth has increased. • Describehow habitat destruction affects biodiversity. • Give two examples of how pollution affects humans.

7. Chapter 21 Section1 Environmental Problems Pollution • An unwanted change in the environment caused by substances, such as wastes, or forms of energy, such as radiation, is called pollution. Anything that causes pollution is called a pollutant. • Some pollutants are produced by natural events, such as volcanic eruptions. Many pollutants are human-made. Pollutants may harm plants, animals, and humans.

8. Chapter 21 Section1 Environmental Problems Pollution, continued • Garbage The average American throws away more trash than the average person in any other nation –– about 12 kg of trash a week. This trash often goes to a landfill. • Landfills often contain medical waste, lead paint, and other hazardous wastes. Hazardous waste includes wastes that can catch fire, eat through metal, explode, or make people sick.

9. Chapter 21 Section1 Environmental Problems Pollution, continued • ChemicalsPeople need and use many chemicals. The same chemicals that help people may harm the environment. • High-Powered WastesNuclear power plants provide electricity to many homes and businesses. The plants also produce radioactive wastes. • Gases Since the Industrial Revolution, the amount of carbon dioxide in the atmosphere has increased, trapping heat around the Earth.

10. Chapter 21 Section1 Environmental Problems Pollution, continued • Gases Since the Industrial Revolution, the amount of carbon dioxide in the atmosphere has increased, trapping heat around the Earth. • Noise Some pollutants affect the senses. These pollutants include loud noises. Noise pollution affects your ability to hear and think clearly, and it may damage your hearing.

11. Chapter 21 Section1 Environmental Problems Greenhouse Effect Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

12. Chapter 21 Section1 Environmental Problems Resource Depletion • Some of Earth’s resources are renewable, but other resources are nonrenewable. A renewable resource is one that can be used over and over, or has an unlimited supply. • A nonrenewable resource is one that cannot be replaced or that can be replaced only over thousands or millions of years. These resources will become more expensive as they become harder to find.

13. Chapter 21 Section1 Environmental Problems Resource Depletion, continued • Renewable or Nonrenewable?Scientists used to think that fresh water was a renewable resource. However, in some areas, water supplies are being used faster than they are being replaced. • Scientists are working on ways to keep these water supplies from being used up.

14. Chapter 21 Section1 Environmental Problems Exotic Species • People may carry plant seeds, animals eggs, or adult organisms with them as they move from one part of the world to another. • An organism that makes a home for itself in a new place outside its native home is an exotic species. Exotic species often thrive in new places, and can become pests and compete with native species.

15. Chapter 21 Section1 Environmental Problems Human Population Growth • Overpopulation happens when the number of individuals becomes so large that the individuals can’t get the resources they need to survive. Some people argue that there may eventually be too many people on Earth.

16. Chapter 21 Section1 Environmental Problems Habitat Destruction • When land is cleared for construction, crops, mines, or lumber, organisms that were living in the areas may be left without food and shelter. These organisms may die. • An organism’s habitat is where it lives. Every habitat has a number and variety of organisms, or biodiversity. If a habitat is damaged or destroyed, biodiversity is lost.

17. Chapter 21 Section1 Environmental Problems Habitat Destruction, continued • Forest Habitats Trees provide humans with oxygen, lumber, food, rubber, and paper. For some of these products, trees must be cut down. Deforestation is the clearing of forest lands. • Marine Habitats Many people think of oil spills when they think of pollution in marine habitats. Spilled oil pollutes both open waters and coastal habitats. In addition to oil, chemicals and plastics are sometimes dumped into marine habitats.

18. Chapter 21 Section1 Environmental Problems Effects on Humans • Pollution and habitat destruction also affect humans. Sometimes, the effect is immediate, Sometimes, the damage is not apparent right away. • Anything that harms other organisms may eventually harm people, too. Caring for the environment means being aware of what is happening now and looking ahead to the future.

19. Chapter 21 Section2 Environmental Solutions Bellringer • Imagine that you have just finished reading a magazine. Write down at least two things you can do with the magazine that would be preferable to throwing it in the trash. • Write your responses in your science journal.

20. Chapter 21 Section2 Environmental Solutions Objectives • Explain the importance of conservation. • Describe the three Rs. • Explain how biodiversity can be maintained. • List five environmental strategies.

21. Chapter 21 Section2 Environmental Solutions Conservation • One way to care for the Earth is conservation. Conservation is the preservation and wise use of natural resources. • Conservation helps reduce waste and pollution. Conservation can help prevent habitat destruction. The three Rs describe three ways to conserve resources: Reduce, Reuse, and Recycle.

22. Chapter 21 Section2 Environmental Solutions

23. Chapter 21 Section2 Environmental Solutions Reduce • Reducing Waste and Pollution As much as one-third of the waste produced by some countries is packaging material. Products can be wrapped in less paper and plastic to reduce waste. • Reducing the Use of Nonrenewable ResourcesSome scientists are looking for sources of energy that can replace fossil fuels. In some parts of the world, solar energy can be used to power homes.

24. Chapter 21 Section2 Environmental Solutions Reuse • Reusing Products You might be surprised at how many materials can be reused. For example, every time you reuse a plastic bag, one bag fewer needs to be made. • Reusing WaterOne way to reclaim water is to use organisms to clean the water. These organisms include plants and filter-feeding animals, such as clams.

25. Chapter 21 Section2 Environmental Solutions Recycle • The recovery of valuable or useful materials from waste or scrap is called recycling. • Recycling Trash Plastics, paper, aluminum, wood, glass, and cardboard are examples of materials that can be recycled. • Recycling ResourcesWaste that can be burned can also be used to generate electricity. Electricity is generated in waste-to-energy plants.

26. Chapter 21 Section2 Environmental Solutions Maintaining Biodiversity • Protecting Species One way to maintain biodiversity is to protect individual species. In the United States, a law called the Endangered Species Act was designed to do just that. • Protecting HabitatsEach organism is part of a huge, interconnected web of organisms. The entire web should be protected to protect these organisms.

27. Chapter 21 Section2 Environmental Solutions Environmental Strategies • Reduce pollution. • Reduce and pesticide use. • Protect habitats. • Learn about local issues. • Develop alternative energy sources.

28. Chapter 21 Section2 Environmental Solutions Environmental Strategies, continued • What You Can DoReduce, reuse, and recycle. Protect the Earth. These are jobs for everyone. Children as well as adults can help clean up the Earth. • The following slide offers some suggestions for how you can help.

29. Chapter 21 Section2 Environmental Solutions

30. Chapter 21 Environmental Problems and Solutions Concept Map Use the terms below to complete the concept map on the next slide.

31. Chapter 21 Environmental Problems and Solutions

32. Chapter 21 Environmental Problems and Solutions

33. End of Chapter 21 Show

34. Standardized Test Preparation Chapter 21 Reading Read each of the passages. Then, answer the questions that follow each passage.

35. Standardized Test Preparation Chapter 21 Passage 1The scientist woke up and jogged over to the rain forest. There she observed the water-recycling experiment. She took a swim in the ocean, after which she walked through a mangrove forest on her way home. At home, she ate lunch and went to the computer lab. From the lab, she could monitor the sensors that would alert her if any part of the ecosystem failed to cycle properly. This monitoring was very important to the scientist and her research team because their lives depended on the health of their sealed environment.

36. Standardized Test Preparation Chapter 21 1. Based on the passage, the reader can conclude which of the following? AThe scientist lives in an artificial environment. BThe scientist lives by herself. CThe scientist and her research team are studying a newly discovered island. DThe scientist does not rely on the health of her environment.

37. Standardized Test Preparation Chapter 21 1. Based on the passage, the reader can conclude which of the following? AThe scientist lives in an artificial environment. BThe scientist lives by herself. CThe scientist and her research team are studying a newly discovered island. DThe scientist does not rely on the health of her environment.

38. Standardized Test Preparation Chapter 21 2. Which of the following statements is a fact in the passage? FThe scientist is scared that her environment is being destroyed. GThe scientist depends on sensors to alert her to trouble. HThe scientist lives in an open environment. IThe scientist eats lunch at home every day.

39. Standardized Test Preparation Chapter 21 2. Which of the following statements is a fact in the passage? FThe scientist is scared that her environment is being destroyed. GThe scientist depends on sensors to alert her to trouble. HThe scientist lives in an open environment. IThe scientist eats lunch at home every day.

40. Standardized Test Preparation Chapter 21 3. Based on the passage, which of the following events happened first? AThe scientist walked through the mangrove forest. BThe scientist checked the water-recycling experiment. CThe scientist swam in the ocean. DThe scientist ate lunch.

41. Standardized Test Preparation Chapter 21 3. Based on the passage, which of the following events happened first? AThe scientist walked through the mangrove forest. BThe scientist checked the water-recycling experiment. CThe scientist swam in the ocean. DThe scientist ate lunch.

42. Standardized Test Preparation Chapter 21 Passage 2All along the Gulf Coast, marine scientists and Earth scientists are trying to find methods to reduce or eliminate the dead zone. They have made models of the Mississippi River ecosystem that have accurately predicted the data that have since been collected. The scientists have changed the models to see what happens. Continued on the next slide

43. Standardized Test Preparation Chapter 21 Passage 2, continuedFor example, wetlands are one of nature’s best filters. Wetlands take up a lot of the chemicals present in water. Scientists predict that adding wetlands to the Mississippi River watershed could reduce the chemicals reaching the Gulf of Mexico, possibly reducing the dead zone.

44. Standardized Test Preparation Chapter 21 1. Based on the passage, what can you conclude about the dead zone? AIt is found in the Mississippi River. BIt may be prevented by adding wetlands to the Mississippi River watershed. CIt reduces the chemicals reaching the Gulf of Mexico. DIt is not caused by chemicals.

45. Standardized Test Preparation Chapter 21 1. Based on the passage, what can you conclude about the dead zone? AIt is found in the Mississippi River. BIt may be prevented by adding wetlands to the Mississippi River watershed. CIt reduces the chemicals reaching the Gulf of Mexico. DIt is not caused by chemicals.

46. Standardized Test Preparation Chapter 21 2. Based on the passage, which of the following statements about models is true? FModels do not accurately predict data. GScientists do not change models. HScientists use models to make predictions. IModels are always used for research.

47. Standardized Test Preparation Chapter 21 2. Based on the passage, which of the following statements about models is true? FModels do not accurately predict data. GScientists do not change models. HScientists use models to make predictions. IModels are always used for research.

48. Standardized Test Preparation Chapter 21 3. Based on the passage, why did the scientists change their models? Ato predict the effects of adding wetlands to the Mississippi River watershed Bto find out why the dead zone happened Cto eliminate the dead zone Dto predict why there are a lot of chemicals in the Gulf of Mexico

49. Standardized Test Preparation Chapter 21 3. Based on the passage, why did the scientists change their models? Ato predict the effects of adding wetlands to the Mississippi River watershed Bto find out why the dead zone happened Cto eliminate the dead zone Dto predict why there are a lot of chemicals in the Gulf of Mexico

50. Standardized Test Preparation Chapter 21 Interpreting Graphics The table below shows the change in ozone levels between 1960 and 1990 above Halley Bay, Antarctica. Use the table to answer the questions that follow.