2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 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. How to Use This Presentation

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Bellringers Transparencies Standardized Test Prep Math Skills Visual Concepts Resources

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Introduction to Science Chapter 1 Table of Contents Section 1 The Nature of Science Section 2 The Way Science Works Section 3 Organizing Data

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer Even before you started this course, you knew a lot about science because science and its effects surround everyone in our society. To help you tap this knowledge, answer the items below. 1. The term science encompasses many areas of study. Name four branches of science and briefly describe the topics that are studied in each. 2. Computer technology has changed the way many tasks are completed today. Name three other technological advances that have occurred since 1900 that have changed our lives significantly. 3. Scientific laws such as the law of gravity govern our daily lives. Name two additional laws of science that govern our lives. Section 1 The Nature of Science Chapter 1

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 The Nature of Science Objectives Describe the main branches of natural science and relate them to each other. Describe the relationship between science and technology. Distinguish between scientific laws and scientific theories. Explain the roles of models and mathematics in scientific theories and laws. Chapter 1

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How Does Science Take Place? Scientists observe. Scientists plan experiments. Scientists investigate. Scientists test the results. Section 1 The Nature of Science Chapter 1

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How Does Science Take Place? continued Science has many branches. Biological science is the science of living things. Physical science is the science of matter and energy. Earth science is the science of the Earth, the atmosphere, and weather. Science is the knowledge obtained by observing natural events and conditions in order to discover facts and formulate laws or principles that can be verified or tested. Section 1 The Nature of Science Chapter 1

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Natural Science Section 1 The Nature of Science Chapter 1

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Biology Section 1 The Nature of Science Chapter 1

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Physics Section 1 The Nature of Science Chapter 1

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Earth Sciences Section 1 The Nature of Science Chapter 1

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How Does Science Take Place? continued Science and technology work together. Pure science - the continuing search for scientific knowledge. Applied science - the search for ways to use scientific knowledge for practical applications. Technology is the application of science for practical purposes. Section 1 The Nature of Science Chapter 1

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How Does Science Take Place? continued Science is based in observation and logic. We naturally seek knowledge and attempt to explain the reasons the “WHY” of the natural world around us. This attempt at explaining the “WHY” is what scientists call a HYPOTHESIS. Natural Process – Roller Balding…. Section 1 The Nature of Science Chapter 1

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Scientific Theories vs Scientific Laws?? Scientific theory an explanation for some phenomenon that is based on observation, experimentation, and reasoning. Theories answer the question “WHY?” with “Because” To be valid, a theory must: explain past observations predict future occurrences be repeatable Scientific theories answer “WHY?” and can be tested. Section 1 The Nature of Science Chapter 1

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Scientific Theories vs Scientific Laws?? A Scientific Law is a summary of observations. Compare and Contrast Theories and Laws… next slide? The Big Bang Theory (y) The Law of Universal Gravitation (summary) Section 1 The Nature of Science Chapter 1

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Hypotheses, Theories, and Laws?? A “good enough” hypothesis can be renamed THEORY That is to say that a well supported hypothesis that accurately explains the past and predicts the future is termed a theory Can a Hypothesis or Theory ever be renamed a LAW? NO Section 1 The Nature of Science Chapter 1

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Comparing Theories and Laws Section 1 The Nature of Science Chapter 1

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Ways to describe observations… A qualitative statement describes something with words. A quantitative statement describes something with mathematical equations. (numbers) A model is a representation of an object or event that can be studied to understand the real object or event. Scientists use many types of models…examples? Section 1 The Nature of Science Chapter 1

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Models Section 1 The Nature of Science Chapter 1

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Physical, Mathematical, and Conceptual Models Section 1 The Nature of Science Chapter 1

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 The Nature of Science Objectives Review Describe the main branches of natural science and relate them to each other. Describe the relationship between science and technology. Distinguish between scientific laws and scientific theories. Explain the roles of models and mathematics in scientific theories and laws. TP Lab?? Chapter 1

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer Your teacher has given you the following assignment: Investigate the impact on plant growth of adding various amounts of fertilizer to potted plants. Think about what you would need to do to be certain that the fertilizer was having the impact on the plant growth. Then answer the items below. Section 2 The Way Science Works Chapter 1

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer Place a Y besides items that would be part of your plan to investigate plant height and fertilizer. Place a N besides items that will not help you investigate this particular connection. a. _______ Put one plant in a sunny windowsill and one in a dark corner. b. _______ Give plants the same amounts of water. c. _______ Give different plants different amounts of fertilizer without keeping track of which plant got extra fertilizer. d. _______ Use some new plants from seeds and some old plants that have been growing for months. e. _______ Start with plants that are the same size. f. _______ Keep all plants in a similar location. g. _______ Carefully note amounts of fertilizer each plant is given. h. _______ Keep one plant fertilized but with no water. Section 2 The Way Science Works Chapter 1

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer 2. Name at least five tools or supplies will you need to perform this experiment. 3. What quantities will be measured, and what units will you use to record these measurements? Section 2 The Way Science Works Chapter 1

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 The Way Science Works Objectives Understand how to use critical thinking skills to solve problems. Describe the steps of the scientific method. Know some of the tools scientists use to investigate nature. Explain the objective of a consistent system of units, and identify the SI units for length, mass, and time. Identify what each common SI prefix represents, and convert measurements using the Unit Analysis Method. Chapter 1

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Science Skills Critical Thinking Scientists approach a problem by thinking logically. Critical thinking is the ability and willingness to assess claims critically and to make judgments on the basis of objective and supported reasons. Section 2 The Way Science Works Chapter 1

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Science Skills, continued Using the scientific method The scientific method is a general description of scientific thinking rather than an exact path for scientists to follow. Scientific method a series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions Section 2 The Way Science Works Chapter 1

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 The Way Science Works Chapter 1

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Scientific Method Section 2 The Way Science Works Chapter 1

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Science Skills, continued Testing hypotheses Scientists test a hypothesis by doing a controlled experiment. In a controlled experiment, all the factors that could affect the experiment are kept constant except for one change. Hypothesis a possible explanation or answer that can be tested Variable a factor that is changed in an experiment in order to test a hypothesis Section 2 The Way Science Works Chapter 1

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Hypothesis Section 2 The Way Science Works Chapter 1

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Controlled Experiment and Variable Section 2 The Way Science Works Chapter 1

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Conducting experiments - No experiment is a failure I have not failed. I've just found 10,000 ways that won't work. Thomas A. EdisonThomas A. Edison The results of every experiment can be used to revise the hypothesis or plan tests of a different variable. Science depends on repetition. If in doubt, do it again! TP Lab Section 2 The Way Science Works Chapter 1

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Science Skills, continued Using scientific tools There are many tools used by scientists for making observations, including microscopes telescopes spectroscopes particle accelerators computers Section 2 The Way Science Works Chapter 1

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Units of Measurement SI units are used for consistency. Scientists use the International System of Units (SI) to make sharing data and results easier. Section 2 The Way Science Works Chapter 1

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Units and Standards We use a measurement standard so we can compare the measurements. Hands are a convenient measuring tool, but using them can lead to misunderstanding In which field are hands still used as a basis of measurement? How long is a hand? 1.2 Standards of Measurement

38. Section 1.3 Learning Chemistry Metric Conversions Divide by 10 for each step up

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu SI (Le Système Internationale d’Unités) Section 2 The Way Science Works Chapter 1

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method make fractions Kilo1km = 1000 m ** Hecto 1 hm = 100 m Deka1 dam = 10 m Base Unit 1(m, L, g, s, K) ** Deci1 dm = 0.1 m Centi1 cm = 0.01 m ** Milli1 mm = 0.001 m ** Quantity contains a UNIT and a NUMBER Section 2 The Way Science Works Chapter 1

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method Kilo (k) 1000 Hecto (h)100 Deka (da)10 Base Unit (m,g,L,s,K) Deci (d) 0.1 Centi (c)0.01 Milli (m)0.001 Quantity contains a UNIT and a NUMBER Divide by 10 for each step up Multiply by 10 for each step down

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method Conversions A roll of copper wire contains 15 m of wire. What is the length of the wire in centimeters? 1. List the given and unknown values. Known: length in meters, l = 15 m Unknown: length in centimeters = ? Cm Set up the “know to go” approach! Know  = go 15 m = cm Section 2 The Way Science Works Chapter 1

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method 2. Determine the relationship between units. Looking at the table of prefixes used for small measurements, you can find that 1 cm = 0.01 m 3. Fill in the conversion factor and solve. Be sure the units cancel! 15 m = cm 15 m 1.0 cm = 1500 cm 0.01 m Section 2 The Way Science Works Chapter 1

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method 2. Determine the relationship between units. If 1 cm = 0.01 m it also means that 100 cm = 1 m 3. Fill in the conversion factor and solve. Be sure the units cancel! 15 m = cm 15 m 100 cm = 1500 cm 1 m Same answer!! Section 2 The Way Science Works Chapter 1

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Conversion factor possibilities: We first used 1.0 cm because the units cancel. 0.01 m We then used 100 cm because the units cancel! 1 m Which is greater? 1 cm or 0.01 m? Which is greater? 100 cm or 1 m? Simplify 1.0 cm and 100 cm 0.01 m 1 m Multiplicative Identity? Section 2 The Way Science Works Chapter 1

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Metric Conversions: Unit Analysis Method Convert the following quantities. Show your work!! 491 km to meters 50,089,743 ml to liters Section 2 The Way Science Works Chapter 1

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu We can sometimes convert using several steps! Convert 0.054 cm to mm Know to Go! Twice! 0.054 cm = mm Or once… 0.054 cm = mm Convert 1,261,338 mm to km Section 2 The Way Science Works Chapter 1

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu We can sometimes convert using several steps! Convert 1,261,338 cm to km 1,261,338 cm = km Convert 22.3 mm to cm Page 17 #1-7 Skip #5 This works for m, L, g, s, K, etc. Metric System Measurement Mini Lab and Coin Lab Section 2 The Way Science Works Chapter 1

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Units of Measurement, continued Making measurements Many observations rely on quantitative measurements. Length a measure of the straight-line distance between two points Mass a measure of the amount of matter in an object Volume a measure of the size of a body or region in three-dimensional space Weight a measure of the gravitational force exerted on an object Section 2 The Way Science Works Chapter 1

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Volume Section 2 The Way Science Works Chapter 1

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 The Way Science Works Objectives Review Understand how to use critical thinking skills to solve problems. Describe the steps of the scientific method. Know some of the tools scientists use to investigate nature. Explain the objective of a consistent system of units, and identify the SI units for length, mass, and time. Identify what each common SI prefix represents, and convert measurements using the Unit Analysis Method. Chapter 1

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Organizing Data Objectives Interpret line graphs, bar graphs, and pie charts. Use scientific notation and significant figures in problem solving. Understand the difference between accuracy and precision. Identify the significant figures in calculations. Chapter 1

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer Imagine your teacher asked you to study how providing different amounts of fertilizer affected the heights of plants. You perform a study and collect the data shown in the table below. Use this data to answer the items that follow. Section 3 Organizing Data Chapter 1

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bellringer, continued 1. Which amount of fertilizer produced the tallest plants? 2. Which amount of fertilizer produced the smallest plants? 3. Plot the data on a grid like the one below. 4. Draw a line graph that describes the overall trend as more fertilizer is added to the plants. 5. Draw a vertical bar graph with the same data. 6. Present these data on a pie chart. 7. Explain which graph gives the best presentation. Section 3 Organizing Data Chapter 1

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Presenting Scientific Data Line graphs are best for continuous change. Line graphs are usually made with the x-axis showing the independent variable and the y-axis showing the dependent variable. The values of the dependent variable depend on what happens in the experiment. The values of the independent variable are set before the experiment takes place. Section 3 Organizing Data Chapter 1

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Line Graph Section 3 Organizing Data Chapter 1

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Presenting Scientific Data, continued Bar graphs compare items. A bar graph is useful for comparing similar data for several individual items or events. A bar graph can make clearer how large or small the differences in individual values are. Section 3 Organizing Data Chapter 1

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Bar Graph Section 3 Organizing Data Chapter 1

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Presenting Scientific Data, continued Pie charts show parts of a whole. A pie chart is ideal for displaying data that are parts of a whole. Data in a pie chart is presented as a percent. Section 3 Organizing Data Chapter 1

60. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Writing Numbers in Scientific Notation Scientific notation is a method of expressing a quantity as a number multiplied by 10 to the appropriate power. _.__ X 10 n Some powers of 10 and their decimal equivalents are shown below. 10 3 = 1000 (1 with three 0’s behind) 10 2 = 100 10 1 = 10 10 0 = 1 10 -1 = 0.1 10 -2 = 0.01 10 -3 = 0.001 (1 with three 0’s in front – sort of) Section 3 Organizing Data Chapter 1

61. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills Writing Scientific Notation The adult human heart pumps about 18 000 L of blood each day. Write this value in scientific notation. _.__ X 10 n 1. List the given and unknown values. Given: volume, V = 18 000 L Unknown: volume, V = ?.? x 10 ? L 2. Write the form for scientific notation. V = _.__ X 10 n ORV = ?.? x 10 ? L 3. Insert the known values into the form, and solve. (1.8 x 10 000) L 1.8 x 10 4 L Section 3 Organizing Data Chapter 1

62. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills, continued Write the following numbers in scientific notation: 1.2200 2.90000 3.40 4.0.007 5.0.0000000000000000000000001 6.Page 23 # 1, 2 Section 3 Organizing Data Chapter 1

63. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Scientific Notation Section 3 Organizing Data Chapter 1

64. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills Using Scientific Notation Your state plans to buy a rectangular tract of land measuring 5.36 x 10 3 m by 1.38 x 10 4 m to establish a nature preserve. What is the area of this tract in square meters? 1. List the given and unknown values. Given: length, l = 1.38 x 10 4 m width, w = 5.36 x 10 3 m Unknown: area, A = ? m 2 Section 3 Organizing Data Chapter 1

65. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills, continued 2. Write the equation for area. A = l  w 3. Insert the known values into the equation, and solve. A = (1.38  10 4 m) (5.36  10 3 m) Regroup the values and units as follows. A = (1.38  5.36) (10 4  10 3 ) (m  m) When multiplying, add the powers of 10. A = (1.38  5.35) (10 4+3 ) (m  m) A = 7.3968  10 7 m 2 A = 7.40  10 7 m 2 Section 3 Organizing Data Chapter 1

66. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Using Significant Figures Accuracy and Precision Accuracy a description of how close a measurement is to the true value of the quantity measured Precision the exactness of a measurement (grouping) Significant figure a prescribed decimal place that determines the amount of rounding off to be done based on the precision of the measurement Section 3 Organizing Data Chapter 1

67. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Accuracy and Precision Section 3 Organizing Data Chapter 1

68. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Accuracy and Precision Section 3 Organizing Data Chapter 1

69. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Accuracy and Precision Section 3 Organizing Data Chapter 1

70. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Using Significant Figures, continued When you use measurements in calculations, the answer is only as precise as the least precise measurement used in the calculation. The measurement with the fewest significant figures determines the number of significant figures that can be used in the answer. Section 3 Organizing Data Chapter 1

71. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills Significant Figures Calculate the volume of a room that is 3.125 m high, 4.25 m wide, and 5.75 m long. Write the answer with the correct number of significant figures. 1. List the given and unknown values. Given: length, l = 5.75 m width, w = 4.25 m height, h = 3.125 m Unknown: Volume, V = ? m 3 Section 3 Organizing Data Chapter 1

72. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills, continued 2. Write the equation for volume. V = l  w  h 3. Insert the known values into the equation, and solve. V = 5.75 m  4.25 m  3.125 m V = 76.367 1875 m 3 The answer should have three significant figures, because the value with the smallest number of significant figures has three significant figures. Section 3 Organizing Data Chapter 1 V = 76.4 m 3

73. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Significant Figures Section 3 Organizing Data Chapter 1

74. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Concept Mapping Section 3 Organizing Data Chapter 1

75. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 Organizing Data Objectives Review Interpret line graphs, bar graphs, and pie charts. Use scientific notation and significant figures in problem solving. Understand the difference between accuracy and precision. Identify the significant figures in calculations. Chapter 1

76. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts 1. During a storm, rainwater depth is measured every 15 minutes. Which of these terms describes the depth of the water? A.controlled variable B.dependent variable C.independent variable D.significant variable Standardized Test Prep Chapter 1

77. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 1. During a storm, rainwater depth is measured every 15 minutes. Which of these terms describes the depth of the water? A.controlled variable B.dependent variable C.independent variable D.significant variable Standardized Test Prep Chapter 1

78. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 2. Why were scientists unable to form a theory that diseases are caused by bacteria before the late fifteenth century? F.No on tried to understand the cause of disease until then. G.Earlier scientists were not intelligent enough to understand the existence of bacteria. H.The existence of microbes could not be discovered until the technology to make high-quality lenses had been developed. I.Doctors believed they understood the disease process, so they would not accept new ideas about the causes. Standardized Test Prep Chapter 1

79. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 2. Why were scientists unable to form a theory that diseases are caused by bacteria before the late fifteenth century? F.No on tried to understand the cause of disease until then. G.Earlier scientists were not intelligent enough to understand the existence of bacteria. H.The existence of microbes could not be discovered until the technology to make high-quality lenses had been developed. I.Doctors believed they understood the disease process, so they would not accept new ideas about the causes. Standardized Test Prep Chapter 1

80. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 3. What is a scientific theory? A.A theory is a guess as to what will happen. B.A theory is a summary of a scientific fact based on observations. C.A theory is an explanation of how a process works based on observations. D.A theory describes a process in nature that can be repeated by testing. Standardized Test Prep Chapter 1

81. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 3. What is a scientific theory? A.A theory is a guess as to what will happen. B.A theory is a summary of a scientific fact based on observations. C.A theory is an explanation of how a process works based on observations. D.A theory describes a process in nature that can be repeated by testing. Standardized Test Prep Chapter 1

82. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 4. When designing a new airplane, experienced pilots use computer simulations to determine how changes from previous designs affect the plane’s handling in flight. What is the advantage of computer simulation over actually building the plane and having pilots test it in actual flight situations? Standardized Test Prep Chapter 1

83. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Understanding Concepts, continued 4. When designing a new airplane, experienced pilots use computer simulations to determine how changes from previous designs affect the plane’s handling in flight. What is the advantage of computer simulation over actually building the plane and having pilots test it in actual flight situations? Answer: The computer simulation provides a model of the new plane so that potential design problems can be corrected without risk to the pilots and without the expense of building an airplane that does not function well. Standardized Test Prep Chapter 1

84. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills Two thousand years ago Earth was believed to be unmoving and at the center of the universe. The moon, sun, each of the known planets, and all of the stars were believed to be located on the surfaces of rotating crystal spheres. Motion of the celestial objects could be predicted based on the complex movement of the spheres that had been determined using observations recorded over many years. 5. Demonstrate why this description of the universe was a useful model to ancient astronomers but not to present-day astronomers. Standardized Test Prep Chapter 1

85. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Skills, continued 5. [See previous slide for question.] Answer: It was useful because it could predict motions of objects in the sky. Standardized Test Prep Chapter 1

86. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics 6. What is the volume of the gas 55 seconds into the experiment? F.15 mL G.24 mL H.27 mL I.50 mL Standardized Test Prep Chapter 1

87. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Units of Measurement, continued SI prefixes are for very large and very small measurements. The table below shows SI prefixes for large measurements. Section 2 The Way Science Works Chapter 1

88. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Units of Measurement, continued The table below shows SI prefixes for small measurements. Section 2 The Way Science Works Chapter 1

89. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Writing Numbers in Scientific Notation, continued Using scientific notation When you use scientific notation in calculations, you follow the math rules for powers of 10. When you multiply two values in scientific notation, you add the powers of 10. When you divide, you subtract the powers of 10. Section 3 Organizing Data Chapter 1

90. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Skills, continued 3. Insert the known values into the form, and solve. First find the largest power of 10 that will divide into the known value and leave one digit before the decimal point. You get 1.8 if you divide 10 000 into 18 000 L. So, 18 000 L can be written as (1.8 x 10 000) L Then write 10 000 as a power of 10. Because 10 000 = 10 4, you can write 18 000 L as 1.8 x 10 4 L. Section 3 Organizing Data Chapter 1