Glencoe Science

Chapter Resources

The Nature of Science Includes: Reproducible Student Pages ASSESSMENT

TRANSPARENCY ACTIVITIES

✔ Chapter Tests

✔ Section Focus Transparency Activities

✔ Chapter Review

✔ Teaching Transparency Activity

HANDS-ON ACTIVITIES

✔ Assessment Transparency Activity

✔ Lab Worksheets for each Student Edition Activity

Teacher Support and Planning

✔ Laboratory Activities

✔ Content Outline for Teaching

✔ Foldables–Reading and Study Skills activity sheet

✔ Spanish Resources ✔ Teacher Guide and Answers

MEETING INDIVIDUAL NEEDS ✔ Directed Reading for Content Mastery ✔ Directed Reading for Content Mastery in Spanish ✔ Reinforcement ✔ Enrichment ✔ Note-taking Worksheets

Glencoe Science Photo Credits Section Focus Transparency 1: (t) Roger Wood/CORBIS, (b) Bettmann/CORBIS; Section Focus Transparency 2: (t)John Reader/Science Photo Library/Photo Researchers, (b)Museum of Paleontology, University of CA, Berkeley

Copyright © by The McGraw-Hill Companies, Inc. All rights reserved. Permission is granted to reproduce the material contained herein on the condition that such material be reproduced only for classroom use; be provided to students, teachers, and families without charge; and be used solely in conjunction with the The Nature of Science program. Any other reproduction, for use or sale, is prohibited without prior written permission of the publisher. Send all inquiries to: Glencoe/McGraw-Hill 8787 Orion Place Columbus, OH 43240-4027 ISBN 0-07-866940-5 Printed in the United States of America. 1 2 3 4 5 6 7 8 9 10 071 09 08 07 06 05 04

Reproducible Student Pages Reproducible Student Pages ■

Hands-On Activities MiniLAB: Try at Home Designing an Experiment . . . . . . . . . . . . . . . . 3 MiniLAB: Observing a Scientific Law . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Lab: Understanding Science Articles . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Lab: Testing Variables of a Pendulum . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Laboratory Activity 1: Problem Solving and a Scientific Method . . . . . 9 Laboratory Activity 2: Probability . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Foldables: Reading and Study Skills. . . . . . . . . . . . . . . . . . . . . . . . . . 15

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Meeting Individual Needs Extension and Intervention Directed Reading for Content Mastery . . . . . . . . . . . . . . . . . . . . . . . 17 Directed Reading for Content Mastery in Spanish . . . . . . . . . . . . . . 21 Reinforcement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Enrichment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Note-taking Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

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Assessment Chapter Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Chapter Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

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Transparency Activities Section Focus Transparency Activities . . . . . . . . . . . . . . . . . . . . . . . . 40 Teaching Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Assessment Transparency Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

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Designing an Experiment Procedure 1. Design an experiment to test the question: Which flashlight battery lasts the longest? 2. In your design, be sure to include detailed steps of your experiment. 3. Identify the independent variable, constants, dependent variable, and control. Independent Variable

Constants

Dependent Variable

Control

Analysis

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1. List the equipment you would need to do your experiment.

2. Explain why you should repeat the experiment.

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Procedure 1. Cut one end from a shoe box. 2. Put the box on the floor. Place a rubber ball in the closed end of the box. 3. Pushing on the closed end of the box, move the box rapidly across the floor. Then suddenly stop pushing.

Analysis 1. What happened when the box stopped?

2. How does Newton’s first law of motion explain this?

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Hands-On Activities

Observing a Scientific Law

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Hands-On Activities

Understanding Science Articles Lab Preview Directions: Answer these questions before you begin the Lab. 1. What will you be reading to discover in this lab?

2. Would you expect to find the names of scientists in the articles you will be reading? Explain.

Scientists conduct investigations to learn things about our world. It is important for researchers to share what they learn so other researchers can repeat and expand upon their results. One important way that scientific results are shared is by publishing them in journals and magazines.

Real-World Question Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

What information about Earth science and scientific methods can you learn by reading an appropriate magazine article?

Materials magazine articles about Earth science topics

Goals ■ ■

Obtain a recent magazine article concerning a research topic in Earth science. Identify aspects of science and scientific methods in the article.

Procedure 1. Locate a recent magazine article about a topic in Earth science research. 2. Read the article paying attention to details that are related to science, research, and scientific methods. 3. What branch of Earth science does the article discuss? 4. Describe what the article is about. Does it describe a particular event or discuss more general research?

5. Are the names of any scientists mentioned? If so, what were their roles? 6. Are particular hypotheses being tested? If so, is the research project complete or is it still continuing? 7. Describe how the research is conducted. What is being measured? What observations are recorded?

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(continued)

1. Explain Are data available that do or do not support the hypotheses? Explain.

2. Infer What do other scientists think about the research?

3. Are references provided that tell you where you can find more information about this particular research or the more general topic? If not, what are some sources where you might locate more information?

Communicating Your Data Prepare an oral report on the article you read. Present your report to the class. For more help, refer to the Science Skill Handbook.

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Conclude and Apply

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Testing Variables of a Pendulum Lab Preview Directions: Answer these questions before you begin the Lab. 1. What will you use to make a pendulum in this lab?

2. What will you use to determine the angle of release? A pendulum is an old, but accurate, timekeeping device. It works because of two natural phenomena—gravity and inertia—that are important in the study of Earth science. Gravity makes all objects fall toward Earth’s surface. Inertia makes matter remain at rest or in motion unless acted upon by an external force. In the following lab, you will test some variables that might affect the swing of a pendulum.

Real-World Question How do the length of a pendulum, the attached mass, and the angle of the release of the mass affect the swing of a pendulum? Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Materials string (60 cm) metal washers (5) watch with a second hand

metric ruler paper clip protractor

Goals ■ ■

Safety Precautions

Procedure 1. Study the three data tables. 2. Bend the paperclip into an S shape and tie it to one end of the string. 3. Hang one washer from the paper clip. 4. Measure 10 cm of string from the washer and hold the string at that distance with one hand.

Manipulate variables of a pendulum. Draw conclusions from experimentation with pendulums.

Table 2

Table 1 The Length of the Pendulum Length of String (cm)

Swings Per Minute Trial 1

Trial 2

Average

Amount of Mass on the Pendulum Units of Mass

10

1

20

2

30

3

40

4

50

5

Swings Per Minute Trial 1

Trial 2

Average

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(continued)

Angle of the Release of the Mass Angle of Release

Swings Per Minute Trial 1

Trial 2

Average

90° 80° 70° 60° 50°

5. Use your other hand to pull back the end of the pendulum with the washer so it is parallel with the ground. Let go of the washer.

6. Count the number of complete swings the pendulum makes in 1 min. Record this number in Table 1. 7. Repeat steps 5 and 6, and record the number of swings in Table 1 under “Trial 2.” 8. Average the results of steps 6 and 7 and record the average swings per minute in Table 1. 9. Repeat steps 4 through 8, using string lengths of 20 cm, 30 cm, 40 cm, and 50 cm. Record your data in Table 1. 10. Copy the data with the string length of 50 cm in Table 2. 11. Repeat steps 5 through 8 using two, three, four, and five washers. Record these data in Table 2. 12. Use 50 cm of string and one washer for the third set of tests. 13. Use the protractor to measure a 90º drop of the mass. Repeat this procedure, calculate the average, and record the data in Table 3. 14. Repeat procedures 12 and 13, using angles of 80º, 70º, 60º, and 50º.

Conclude and Apply 1. Explain When you tested the effect of the angle of the drop of the pendulum on the swings per minute, which variables did you keep constant?

2. Infer which of the variables you tested affects the swing of a pendulum.

3. Predict Suppose you have a pendulum clock that indicates an earlier time than it really is. (This means it has too few swings per minute.) What could you do to the clock to make it keep better time?

Communicating Your Data Graph the data from your tables. Title and label the graphs. Use different colored pencils for each graph. Compare your graphs with the graphs of other members of your class.

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Table 3

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Problem Solving and a Scientific Method

Think back to the last problem you had to solve. You probably used some or all of the steps of a “Scientific Method.” A scientific method is a logical approach to solving problems. Most scientists recognize four basic problem solving steps: (1) determining the problem, (2) testing, (3) analyzing the results, and (4) drawing conclusions.

Strategy You will use the scientific method to determine the density of an ice cube.

Materials ice cubes graduated cylinder graduated beaker alcohol metric ruler balance forceps or tongs water WARNING: Do not ingest alcohol or breathe fumes. Some alcohol is poisonous. Liquid and vapor are extremely flammable.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Procedure 1. In order to solve the problem, you must first determine what it is you need to know. Place an ice cube on the tabletop and make observations. Describe the shape of the ice cube. Using a metric ruler, measure its size. Record them in the data table below.

Ice cube

2. What other information is helpful that cannot be gained from initial observation? You may wish to do some research. A. Define the unknown terms: Density

Mass

Volume 3. Design a test (in this case a procedure) that will enable you to determine the density of an ice cube. Record the steps below. If you need a second trial, record that procedure also.

Observation

A. View on tabletop for 5 minutes B. Shape C. Size D. In water E. In alcohol

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Laboratory Activity 1 (continued) A. B. C. D. E.

Data Collected (framework for writing results) A. Volume of the ice cube: _______________ cubic centimeters (cm3) B. Mass of the ice cube: _______________ grams (g) C. Density of the ice cube: _______________ grams/cubic centimeter (g/cm3) 4. Analyze the results. A. My answer for the density of the ice cube was _______________. B. The accepted value for the density of the ice cube is _______________. C. Now determine the percent error. The percent error is determined by the following formula: Accepted Value minus Calculated Value divided by the Accepted Value times 100. Accepted – Calculated Accepted ✕ 100 D. The percent error is _______________. Conclusion If your percent error is low (under 10%), then your experimental design is acceptable given the materials and the time you had available for completing the task. Knowing the “right” answer to a problem is not always possible. A scientist has to repeat an experiment several times and often will compare the results with others. 5. Did you compare your results with the other students? Did you compare procedures? Do you think you need to change your procedures? What is your conclusion?

Strategy Check Can you recognize the steps of a scientific method? Can you use a scientific method to determine the density of an ice cube?

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Hands-On Activities

Second Trial Procedure

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Probability

Crystals in rocks and cells in plants and animals develop in relatively predictable ways. Other materials behave in unpredictable ways. Gas particles, for instance, move in every direction, bump into obstacles, then fly off in different directions. Scientists make educated guesses about this type of behavior based on the laws of probability. Studying probability helps scientists predict random behavior. Scientists make many observations of the random behavior and find the average of all these observations. They use this average to make predictions about how the material is likely to behave in the future.

Strategy You will use a spinner to determine the direction and distance you will move. You will use probability to interpret your random movements.

Materials cardboard (thin) glue or paste scissors straight pin shirt button pencils (colored) graph paper metric ruler

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Procedure 1. Paste the spinner and pointer section, Figure 1, to the cardboard. 2. Cut out the spinner and the pointer. 3. Push the straight pin upward through the center dot of the spinner. 4. Place the button on the pin and then push the pin through the center of the arrow. 5. Spin the arrow. When it stops, read from the outer dial the direction in which you are to move. Record the direction in Table 1 on the next page. 6. Spin the arrow again. When it stops, read the number of spaces you are to move from the inner dial. Record the number of spaces in Table 1. 7. Record 20 turns (2 spins each turn). This is Trial 1.

8. Spin 20 more turns; record under Trial 2. Spin 20 more turns; record under Trial 3. 9. Start at Point A at the center of the graph paper, and plot your movements for Trial 1. Move diagonally if the direction is northeast, southeast, northwest, or southwest. Move along a grid line if the direction is north, south, east, or west. 10. Using different colored pencils, plot your movements for Trials 2 and 3. Begin plotting each trial at Point A. 11. Measure and record the distances along a straight line from Point A to the end of your random paths. Record the class average also.

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Laboratory Activity 2 (continued) Table 1 Trial 1 Turns

Direction

Spaces

Trial 2 Direction

Spaces

Trial 3 Direction

Spaces

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Distance Class average distance

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Data and Observations

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Laboratory Activity 2 (continued) Questions and Conclusions 1. Were the three distances equal? Did all three paths follow the same direction? 2. Based on your three trials, can you make an accurate prediction of the distance and direction of future paths? 3. Would the average distance of ten paths be more accurate for predicting distance and direction than the average of your three paths? Why?

4. How does the class average compare to your average?

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5. Which is the better prediction, the class average or your average? Explain.

6. Is a scientific law based on probability necessarily incorrect?

Strategy Check Can you predict how far from Point A you will travel based on your three paths? Can you predict random motion using probability?

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The Nature of Science

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Directions: Use this page to label your Foldable at the beginning of the chapter.

hypothesis scientific methods science Earth science variable independent variable constant dependent variable control technology scientific theory scientific law ethics bias The Nature of Science

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Meeting Individual Needs

Meeting Individual Needs

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Directed Reading for Content Mastery

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Overview The Nature of Science

Directions: Complete the concept map by using the words below. scientific theories constants technology hypothesis dependent variables experiments independent variables

Meeting Individual Needs

One scientific method for problem-solving involves developing a

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

1.

which can be the basis of a new

that can be tested by designing

which can lead to

2.

3.

4.

or the use of science for practical purposes

composed of variables such as

or scientific explanations

5.

6.

7.

that change

that do not change

that are measured

Directions: Circle the terms in parentheses that best complete the sentence. 8. Problems that deal with ethics (can, cannot) be solved using scientific methods. 9. Ethics deals with (moral values, scientific facts). 10. There (are, are no) limits to what science can explain.

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Section 1

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Science All Around

Directions: Study the drawing, then circle the words below the drawing that describe topics studied by Earth science.

Earth science topics agriculture precipitation trees rocks hills 18 The Nature of Science

islands the Sun rivers bridges clouds

navigation birds oceans wind maps

fish people boats roads weather

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QQ

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Directed Reading for Content Mastery

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Scientific Enterprise

Directions: Write the correct name of each weather instrument below to match the illustration. hygrometer

barometer

anemometer

thermometer

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Change

dry

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my

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Meeting Individual Needs

1. The ____________________ measures temperature.

V er

y

9

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1

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2. The ____________________ measures atmospheric pressure.

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3. The ____________________ measures wind speed.

% 4. The ____________________ measures the percentage of water vapor in the air. Directions: In the spaces provided, write Yes in front of each question that science can answer and No in front of those that science cannot answer. 5. Is it ethical to use animals in medical experiments? 6. Do humans have more value on Earth than other life forms? 7. What is the distance to the nearest star? 8. Should humans try to colonize other planets? 9. How can more rice be grown on an acre of land? 10. How do trees benefit humans? The Nature of Science

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Key Terms The Nature of Science

Directions: Use the clues below to complete the crossword puzzle. 1 2

3

4 5

7

8

9 10 11

12

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Across 2. The standard to which an experiment’s results can be compared 4. The variable you want to test: ______ variable 6. Problem solving procedures 10. Variable that does not change in an experiment 11. Explanation backed by results obtained from repeated tests or experiments: scientific ______ 12. Factors that can change in an experiment 13. Deals with moral values about what is good or bad 20 The Nature of Science

Down 1. The process of observing and studying things in your world 3. Use of scientific discoveries for practical purposes 5. A personal opinion 7. Type of science that studies Earth and space 8. An educated guess 9. Rule that describes the behavior of something in nature: scientific ______

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Nombre

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Lectura dirigida para Dominio del contenido

Clase

Sinopsis La naturaleza de la ciencia

Instrucciones: Completa el mapa de conceptos usando los siguientes términos. teorías científicas constantes tecnología hipótesis variables dependientes experimentos variables independientes

Satisface las necesidades individuales

Un método científico para resolver problemas involucra el desarrollo de un(a)

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1.

que puede ser la base de un(a) nuevo(a)

que puede probarse diseñando

que puede conducir a

2.

3.

4.

o el uso de la ciencia para usos prácticos

compuestos de variables como

o explicaciones científicas

5.

6.

7.

que cambian

que no cambian

que se miden

Instrucciones: Haz un círculo alrededor del término en paréntesis que mejor complete cada oración. 8. Los problemas de ética (se pueden, no se pueden) resolver usando métodos científicos. 9. La ética trata con (valores morales, hechos científicos). 10. (No existen, Existen) límites para lo que la ciencia puede explicar. La naturaleza de la ciencia

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Nombre

Fecha

Lectura dirigida para

Sección 1

Clase ■

La ciencia nos rodea

Dominio del contenido Instrucciones: Estudia el diagrama y luego encierra en un círculo las palabras que describen temas que estudia la ciencia de la Tierra.

agricultura precipitación árboles botes de vela nubes 22 La naturaleza de la ciencia

Temas de las ciencias de la Tierra islas peces el Sol aves ríos océanos puentes viento mapas tiempo

colinas personas barcos caminos navegación

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Satisface las necesidades individuales



Q
QQ

Nombre

Fecha

Sección 2

Lectura dirigida para

Clase ■

El trabajo científico

Dominio del contenido Instrucciones: Escribe el nombre correcto de cada instrumento para medir el tiempo. Completa la frase que describe cada ilustración.

Rain

dry

96 r

V er

9

06

y

1

104

Fair

Sto

my

termómetro

10

Change

4

anemómetro

2

9

100 8

barómetro

Satisface las necesidades individuales

higrómetro

1. El(La) ____________________ mide la temperatura.

108

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2. El(La) ____________________ mide la presión atmosférica.

% 3. El(La) ____________________ mide la velocidad del viento. 4. El(La) ____________________ mide el porcentaje de vapor de agua en el aire. Instrucciones: En los espacios dados, escribe Sí en frente de cada pregunta que la ciencia puede contestar y No en frente de aquellas preguntas que la ciencia no puede contestar. 5. ¿Es ético el uso de animales en los experimentos de medicina? 6. ¿Tienen más valor los humanos que los demás seres vivos sobre la Tierra? 7. ¿Cuál es la distancia a la estrella más cercana? 8. ¿Deben los humanos colonizar otros planetas? 9. ¿Cómo se puede sembrar más arroz en un acre de tierra? 10. ¿Cómo benefician los árboles a los humanos? La naturaleza de la ciencia

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Nombre

Fecha

Lectura dirigida para Dominio del contenido

Clase

Términos claves La naturaleza de la ciencia

Instrucciones: Usa las claves para completar el siguiente crucigrama.

1 2

3

5

4

7

9

8 10

11 12

13

Horizontales 3. Procedimientos para resolver problemas 6. La variable que quieres probar: variable ______ 8. Factor que puede cambiar en un experimento 9. Conjetura informada 11. Tiene que ver con los valores morales del bien y el mal 13. Variable que no cambia en un experimento

24 La naturaleza de la ciencia

Verticales 1. Uso práctico de los descubrimientos científicos 2. Explicación que se basa en resultados de pruebas y experimentos repetidos: ______ científico 4. El estándar con el cual se comparan los resultados de un experimento 5. Proceso de observar y estudiar cosas del mundo 7. Tipo de ciencia que estudia la Tierra y el espacio 9. Regla que describe el comportamiento de algo en la naturaleza: ______ científica 12. Opinión personal

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Reinforcement

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Science All Around

Directions: Answer the following questions on the lines provided. 1. What is science?

Meeting Individual Needs

2. Define the word hypothesis. Give an example of a possible hypothesis.

3. List the steps of the scientific method.

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4. What are the constants in an experiment?

5. Compare dependent variable and independent variable.

6. Define control.

7. Define technology. Give an example of a technological advancement that you use daily.

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Scientific Enterprise

Directions: Complete the paragraphs by writing the correct terms in the spaces. Early people observed their surroundings and relied on 1. ______________________________ to explain storms, volcanoes, and seasons. When people observed seasonal phenomena, they developed a 2. ______________________________ of about 365 days. Knowledge collected over time about weather evolved into the science of 3. ______________________________. Instruments

was probably the first weather instrument. In the 1600s in Italy other instruments were developed to set up weather stations. The 5. ______________________________ measures air pressure. The 6. ______________________________ measures temperature. Water vapor in the air is measured by a 7. ______________________________. Wind speed is measured by an 8. ______________________________. The first American to suggest weather could be predicted was 9. ______________________________. The Weather Bureau of the late 1800s became the 10. ______________________________. Scientists form and test 11. ______________________________. New 12. ______________________________ is gathered over long periods of time. When tests are repeated, an explanation and hypothesis becomes a 13. ____________________. When a rule is proposed to describe the behavior of something in nature, it is called a 14. ____________________. Usually laws describe what will happen but don’t give an 15. ____________________.

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Meeting Individual Needs

were developed to measure weather phenomena. The 4. ______________________________ gauge

Name

Enrichment

Saving the Ozone Layer

There is no doubt that chlorofluorocarbons (CFCs) in the atmosphere are contributing to the depletion of Earth’s ozone layer. Why does this matter? Atmospheric ozone, most of which is concentrated in the stratosphere about 15–30 kilometers above Earth’s surface, absorbs the most dangerous ultraviolet light (UV-B) from the Sun. UV-B is known to cause skin cancer and to damage eyes. It also harms various crops and forms of marine life. The CFCs, which were manufactured for use as refrigerants and other applications, can eventually be carried by winds high into the stratosphere. Normally they are very stable, but in the stratosphere they break down and release atomic chlorine. The chlorine atoms then react with ozone molecules. It is estimated that it takes only one chlorine atom to destroy 100,000 ozone molecules.

Early Experiments Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Class

This knowledge came about because of experiments begun in the 1880s when scientists began to find ways of detecting and measuring the various gases present in the atmosphere. One experiment lead to another as new hypotheses were tested and either discarded or proven true. It was at this time that ozone was shown to be the substance protecting Earth from UV-B radiation. In 1970, a British scientist was able to detect CFCs carried by winds to many parts of the globe. This is not surprising; at that time nearly 1 billion kilograms of CFCs were being manufactured yearly. No one yet knew the danger they posed.

Rowland-Molina Hypothesis Two scientists, Sherwood Rowland and Mario Molina, decided to find out what happened to all the CFCs. Basing their studies on work previously done by many other scientists, they asserted that CFC chlorine atoms were combining with and destroying ozone molecules in the stratosphere. Not all scientists agreed. Some advanced the hypothesis that chlorine from volcanic eruptions and other natural sources accounted for ozone depletion. Two years later the Rowland-Molina hypothesis was confirmed by the National Academy of Sciences.

Hole Over Antarctica In 1984, a hole in the ozone layer was discovered over Antarctica. This was verified the following year by a NASA satellite. The danger was now real. More than 160 countries agreed to reduce the amount of CFCs released into the atmosphere. Deadlines have been set for their complete elimination. In the meantime, there has been a new hypothesis regarding the effect of global warming on ozone depletion, and new experiments will have to be conducted. It will be many years before the ozone layer once again fully protects Earth from UV-B radiation. Had it not been for the curiosity of scientists like Rowland and Molina and their painstaking approach to the scientific testing, it might not have been discovered until it was too late.

1. Why didn’t scientists know before the 1880s the role that ozone plays in the atmosphere? 2. What is it in CFCs that destroys ozone? 3. Why were nearly 1 billion kilograms of dangerous CFCs being manufactured in 1970?

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Inductive Reasoning

When you draw a conclusion based on a number of observations, you are using inductive reasoning. By this process, you make a general statement based on specific examples. The following are examples of inductive reasoning.

What percent of the seeds in a package will sprout?

Observations:

In three tests of 100 seeds each, 95, 89, and 92 seeds sprouted.

Conclusion:

About 92% of the seeds in a package will sprout.

Problem to solve:

Which of the two cars in a race is faster—the blue car or the red car?

Observations:

In 5 tests of 10 laps each, with the same driver, the blue car’s time was always faster.

Conclusion:

The blue car is the faster car.

The conclusions that result from inductive reasoning only reflect the observations that were used to make them. If other factors would affect the conclusion but were not observed, the process may produce misleading results. 1. Suppose all of the seed tests were done at the same time in the same type of soil and weather conditions. What limitations would that put on the conclusion that 92% of the seeds in a seed package will sprout?

2. What if, unknown to the experimenter, a wheel on the red car was loose? What effect could that fact have on the validity of the conclusion that the blue car is the faster car?

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Meeting Individual Needs

Problem to solve:

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Science All Around

A. Scientists are like ____________________ trying to solve mysteries. 1. Scientists gather information and __________________ in their search for answers to questions. 2. A ____________________ is an educated guess about a possible solution to a mystery.

Meeting Individual Needs

B. Scientists use a problem-solving procedure called the ___________________________; it includes identifying a problem, gathering information, making hypotheses, testing the hypotheses, analyzing the results, and drawing conclusions. C. _________________ is a process of observing, studying, and thinking about things to gain knowledge to better understand the world. 1. Any attempt to find out _____________ and _____________ things look and behave the way they do is a performance of science. 2. _____________ is the study of Earth and space.

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D. Testing, or _______________________, is an important part of science. 1. ___________________ are the different factors that can change in an experiment. a. An experiment should be designed so that only ___ variable at a time is tested. b. The variable that changes, the one being tested in an experiment, is the ______________________________. c. Constants are variables that _________________ change. d. A ____________________________ is the variable being measured. 2. A _________________ is a standard to which results can be compared; the same experiment done with the same variables, except it omits the ____________________ variable. 3. For results to be valid or reliable, tests should be repeated _________________ times. 4. ___________________ and recording data and discoveries are important parts of an experiment. a. Data and observations must be analyzed to draw _____________________. b. Unexpected _________________ may be important and should be recorded, as well.

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Note-taking Worksheet (continued) E. ____________________—use of scientific discoveries for practical purposes such as making pottery or extracting metals from rocks 1. Technology is ______________________, meaning it can be applied to new situations. 2. Earth scientists and biologists use information from ____________________ to gather weather data and track animals.

Section 2

Scientific Enterprise

such as weather or seasons. 1. Early civilizations used observations of recurring natural events like floods and the appearance of stars to create ___________________. 2. Civilizations advanced to the use of _____________________ to measure things observed and developed a scientific approach for testing inferences, or conclusions. B. _____________________, the study of weather, is a science developed over time. 1. A ____________________, used as early as 321 B.C., was probably the first weather instrument; in the late 1600s, Italian scientists developed the barometer, thermometer, hygrometer, and anemometer. 2. Benjamin Franklin was the first American to suggest that weather could be ___________________. a. By 1849, volunteer weather observers were telegraphing information to the _____________________ _____________________. b. In 1850, the secretary of the Smithsonian Institution began drawing weather ______________. 3. The U.S. Weather Bureau was formed and functioning by the late 1800s and was renamed the __________________________________ in 1970 when it became part of the National _________________ and Atmosphere Administration (NOAA).

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Meeting Individual Needs

A. Early people believed mythological ______________ were responsible for natural phenomena

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Note-taking Worksheet (continued) C. Scientific knowledge _________________ as testing procedures and instruments improve. 1. An explanation or model backed by results obtained from many tests or experiments is called a ___________________________. 2. A ________________________ is a rule that describes the behavior of something in nature, usually without explaining why the behavior occurs. D. Science cannot answer all questions.

Meeting Individual Needs

1. ________________ deals with moral values about what is good or bad. 2. ________________________ systems deal with religious questions that science cannot answer, such as: Do humans have more value than other life forms? E. It is important to prevent ______________, or personal opinion, from influencing scientific observations. 1. Ethical and unbiased scientists keep detailed notes and allow other scientists to __________________ their work. 2. Scientific _______________ includes making up data, changing experiment results, or

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taking credit for another’s work.

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Assessment Assessment 32 The Nature of Science

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Chapter Review

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Part A. Vocabulary Review Directions: Write the correct term in the spaces beside each definition. 1. a prediction or statement that can be tested

___ ___ ___ ___ ___ ___ ___ ___ ___ ___

3. a factor in an experiment that can change

___ ___ ___ ___ ___ ___ ___ ___

4. a standard to which experimental results can be compared

___ ___ ___ ___ ___ ___ ___

5. variable being measured

___ ___ ___ ___ ___ ___ ___ ___ ___

6. variable that changes

___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___

7. problem-solving by following steps to draw a conclusion

___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___ ___

8. a process of observing, studying, and thinking about things to gain knowledge

___ ___ ___ ___ ___ ___ ___

9. personal opinion that may affect experiments

___ ___ ___ ___.

Assessment

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2. use of knowledge to make products or tools ___ ___ ___ ___ ___ ___ ___ ___ ___ ___

Part B. Concept Review Directions: Number these steps for doing an experiment in the correct order in the blanks provided. 1. Draw conclusions. 2. Form a hypothesis. 3. Gather information (research). 4. Test your hypothesis. 5. Recognize the problem. 6. Analyze your data.

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Chapter Review (continued) Directions: Correctly complete each sentence by underlining the best of the three choices in parentheses. 7. Scientists use (observations, experiments, observations and experiments) to find answers to problems. 8. The variables that do not change in an experiment are called (dependent, independent, constants). 9. An instrument used to measure air pressure is a (thermometer, barometer, hygrometer). 10. Scientific (theories, hypotheses, laws) describe what will happen, but do not explain why. 11. (Ethics, Science, Mathematics) deals with moral values about what is good or bad.

Directions: Answer the following questions using complete sentences. 12. How do scientists deal with ethics in their jobs?

Assessment 14. Explain the difference between scientific theories and scientific laws.

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13. What does the term “transferable technology” mean? Give an example.

Transparency Activities

Transparency Activities

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An Investigation Amply Rewarded

Transparency Activities

1. Why is it important for everyone on a research team to know and follow the same steps? 2. Using King Tut’s tomb as an example, how might fieldwork and lab work go hand in hand? 3. What sort of equipment might be useful to an archaeologist? 40 The Nature of Science

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Tutankhamen’s tomb, the only royal Egyptian tomb ever found intact, is one of the most famous archaeological discoveries. The tomb was finally opened in 1922 after years of painstaking excavations based on careful research. Following similar steps can help scientists unravel mysteries both modern and ancient.

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Hoax or Not

Transparency Activities

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On the left is a skull found in 1912 that many scientists accepted as a genuine fossil. Named Piltdown Man, it was proven to be a hoax in 1953. On the right is a fossil of Archaeopteryx. One scientist alleged it to be a forgery carved in the 1800s, but data from an electron microscope revealed fossilized bacteria on Archaeopteryx.

1. What might have tempted scientists to view Piltdown Man as a genuine fossil? 2. Why do the fossilized bacteria hint that Archaeopteryx is not a forgery? 3. What kinds of advancements help scientists to continue learning? The Nature of Science

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Scientific Method

Identify a problem

Gather information (research)

Test the hypothesis

Analyze the results Transparency Activities

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Make a hypothesis

Draw conclusions

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(continued)

1. What is the name of the problem-solving procedure that scientists use? 2. Why are scientific methods used?

3. What is a hypothesis?

4. In an experiment, which variable is the one that the experimenter changes? Which variable is measured?

Transparency Activities

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5. What are two problems in everyday life that could be solved using scientific methods?

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The Nature of Science

Directions: Carefully review the table and answer the following questions. Steps in the Scientific Method Steps Identifying the problem Researching the problem

Pick a question to be tested Collect information

Forming a hypothesis

Make an informed guess about the results

Testing the hypothesis

Do an experiment and collect data

Analyzing the results

Arrange the data and compare the data to the hypothesis

Conclusion

From the analysis of the data, suggest a final answer

1. According to the table, looking up information on the computer about different types of soil is an example of ___. A identifying a problem C analyzing results B researching D hypothesis testing 2. According to the table, which step does not involve data collected in an experiment? F identifying a problem H analyzing results G hypothesis testing J conclusion

Transparency Activities

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Procedures

3. Which step of the scientific method presents the final results of your hypothesis? A identifying a problem C hypothesis testing B researching D conclusion The Nature of Science

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