Chapter 1: The Nature of Science

Chapter 1: The Nature of Science

Table of ContentsTable of Contents

Section 1-2 Science in Action

A. Scientific Methods1. Step-by-step procedures of scientific problem

solving are called scientific methods.

2. Solving any problem scientifically involves several steps.

3. The steps used can vary from situation to situation and aren’t always done in the same order.

Ch 1-2 Science in ActionCh 1-2 Science in Action

A. Scientific Methods

.


B. Recognize the Problem

1. The first step in using a scientific approach to solving a problem is recognizing a problem.

2. A scientific problem is a question that can be answered using scientific methods.

3. To solve a problem, scientists must do research using various sources of information.


C. Observe

1. In order to be able to answer the question, a scientist needs to plan and carry out an experiment.

2. First, he or she must make and record careful observations about the subject.


C. Observe3. Observations can be bits of information you

gather with your senses.

4. Most scientific observations are made with your eyes and ears.


5. You also can observe with your senses of touch, taste, and smell.

D. Infer

1. Observations often lead to inferences.

2. An inference is a conclusion based on what you observe.


E. Form a Hypothesis

1. After a problem is identified, a scientist might make a hypothesis.

2. A hypothesis (hi PAH thuh sus) is a statement that can be tested.


3. Hypotheses are based on observations, research, and prior knowledge of a problem.

4. Sometimes more than one hypothesis can be developed.

E. Form a Hypothesis5. Hypotheses differ from two other scientific

statements—scientific theories and scientific laws.


F. Test Your Hypothesis1. An experimental investigation is a series

of carefully planned steps used to test a hypothesis.


2. In any experiment, it’s important to carefully consider what resources you will use and how to conserve them.

3. It’s also important to keep everything the same except for the item or variable you are testing so that you’ll know which variable caused the results.

F. Test Your Hypothesis


5. For example, in an experiment, similar-sized fig plants received the same amount of sunlight.

4. A variable that you change in an experiment is calledthe independent variable.



7. The hypothesis to test is that fig plants grow best when watered only once a week.

6. They were planted in similar containerswith the same type and amount of soil.


8. The independent variable is the number of times he waters each plant in a week.


9. The growth of the plants is the dependent variable.

10. A dependant variable is a variable, or outcome, that depends on what happens in the experiment when the independent variable is used.

G. Plan the Experiment

1. In order to test only one variable at a time, scientists often use constants.


2. Constants are factors in an experiment that stay the same.

G. Plan the Experiment3. Some experimental investigations also have

a control. A control is a standard used for comparison.


4. If a scientist wished to study the chemical makeup of a soil sample. A control soil—one of known chemistry— could be analyzed first.

5. That way, data from the sample of interest could be directly compared to data from the control soil.

H. Do the Experiment

1. In the fig plant experiment, plant A would only be watered once, at the beginning of the experiment.


2. A second fig plant, plant B, would get watered everyday.

3. The third fig plant, plant C, would get watered once each week. The experiment would last one month.

H. Do the Experiment4. Tables can be used for recording observations.


5. These will list each plant and the number of times it was to be watered.

Plant Date Watered

Plant Height

Leaf Color

Number of Leaves

Dropped

A 9/3/2014 10.5 Green 0

B

C

H. Do the Experiment


6. Observations, which would include the height of each plant, the color of its leaves, and the number of leaves it dropped, if any, should be recorded.

Plant Date Watered

Plant Height

Leaf Color

Number of Leaves

Dropped

A 9/3/2014 10.5 Green 0

B

C

I. Analyze Your Data1. Data are collected during any scientific study.


2. Some data are numeric values such as the length of an object or the temperature of a liquid.

3. Other data you collect may include observations that use adjectives and phrases such as faster, smaller, not as well as, and greener.

4. An experimenter must record and study the data collected before he or she can draw conclusions about an experiment.

I. Analyze Your Data5. By the end of the month in the fig experiment,

the leaves still left on the plant that was watered only once were brown and shriveled. It had lost most of its leaves.


6. The plant that was watered everyday had a few leaves left on its branches, but these leaves didn’t look too healthy.

I. Analyze Your Data

7. The plant that was watered once each week had grown the tallest.


8. Many healthy green-and-white leaves extended from its branches.

J. Draw Conclusions and Communicate

1. A conclusion is a statement based on what is observed.


2. It can be concluded in the fig experiment that not watering a plant enough causes the leaves to dry out and die.

3. Watering a plant too much also causes the leaves to die.

4. Watering the plant once a week seems to be the best schedule, of those tested, for a fig plant.

5. The hypothesis was supported.


6. But in order to make sure his conclusions were valid, he should repeat his experiment.

7. An important step in the scientific process is to communicate the results of an investigation.

J. Draw Conclusions and Communicate

K. Laboratory Safety • In your science class, you will perform many

types of investigations.


• However, performing scientific investigations involves more than just following specific steps.

• You also must learn how to keep yourself and those around you safe by obeying the safety symbol warnings.


K. Laboratory Safety


L. Good Safety Habits

1. Find and follow all safety symbols before you begin and investigation.

2. Always wear an apron and goggles to protect yourself from chemicals, flames, and pointed objects.

3. Keep goggles on until activity,, cleanup, and hand washing are complete.


L. Good Safety Habits

4. Always slant test tubes away from yourself and others.

5. Never eat, drink, or put on make up in the lab.6. Report all accidents to your teacher.7. Always wash your hands after working in the

lab.

Section CheckSection Check

Question 1

List the steps in the scientific method.


Question 2What is an independent variable in an experiment?


Question 3

Compare and contrast an observation and an inference.

To advance to the next item or next page click on any of the following keys: mouse, space bar, enter, down or forward arrow.

Click on this icon to return to the table of contents

Click on this icon to return to the previous slide

Click on this icon to move to the next slide

Click on this icon to open the resources file.

HelpHelp

Click on this icon to go to the end of the presentation.

End of Chapter Summary File

Chapter 1: The Nature of Science

Documents

Transcript of Chapter 1: The Nature of Science