The Nature of Science

Living Environment

What is Science?

• Science: knowledge based on the study of nature

• Theory: explanation of a natural phenomenon supported by many observations and experiments over time

The Scientific Method

1. State the problem or question2. Research the problem or question3. State the hypothesis4. Test the hypothesis (Do the experiment)5. Collect data6. Make sense of the results (Analyze)7. State the conclusions8. Repeat the work

Scientific Method Rap

*Handout*

The Scientific Method

1. State the problem or question

• Will a bean plant grow taller in direct sunlight?

The Scientific Method

2. Research the problem or question

• You might find a gardener for advice on varieties and growing conditions.

The Scientific Method

3. State the hypothesis• Hypothesis: a testable explanation of a

situation

• If bean plants are planted in direct sunlight, then they will grow taller than bean plants planted in indirect sunlight.

The Scientific Method

4. Test the hypothesis (Do the experiment)

• Control group: group used for comparison (“the normal”)

• Beans grown in partial sunlight

• Experimental/Variable group: group exposed to the factor being tested

• Beans grown in direct sunlight

The Scientific Method

4. Test the hypothesis (Do the experiment)

• Independent variable: factor that is being changed (manipulated)

• Amount of sunlight

• Dependent variable: factor that is being measured

• Height of bean plant

• Constant: factor that remains the same (fixed)• Amount of water, pH of soil, quality of dirt, etc.

The Scientific Method5. Collect the data

– Data: information gained from observations

• Record observations and measurements in a data table

– Record height of bean plants in data table.

The Scientific Method

6. Analyze the results

• Create graphs to look for patterns in the data

• Look for possible errors– Plot bean plant height vs. time

The Scientific Method

7. State the conclusion

• Summarize findings from the analysis of data collected

– Bean plants grow taller in direct sunlight.

The Scientific Method

8. Repeat the work

• Conduct the experiment again to verify results

Validity & Reliability

• What can increase the validity & reliability of an experiment??1. Large sample size2. Repeating the experiment3. Peer review

Peer review: process by which, procedures used during an experiment and the results are evaluated by other scientists who are in the same field and conducting similar research