1. An Organized Approach to Solving Problems
SCIENTIFIC METHOD
An Organized Approach to Solving Problems

2. Scientific Method
Organized problem solving
Not a single method

3. Steps of the Scientific Method
Define the Problem
Collect Information About the Problem
Form a Hypothesis
Experiment
Collect Results
Conclusion
Repeat

4. Step 1. Problem What are to trying to find out?
- Usually based on observations
- stated as a question
Example: I notice that on warm nights crickets seem
to chirp more often
Problem = Does temperature affect the rate of cricket chirps?

5. Step 2. Collect Information About the Problem
Information can be gathered from:
- your own observations
- published research
textbooks, articles, internet etc…

6. Step 3. Form a Hypothesis A possible solution to your problem
Must make a prediction
Must be possible to be disproved
- UFOs exist is not a scientific hypothesis because it is impossible to disprove

7. Formal Hypothesis
A formal hypothesis used in an experiment should be stated in If…Then form.
- It relates directly to the experiment to be conducted and explains the expected outcome
-If I do this…..then that will happen.
Example: If I raise the temperature I keep crickets in, then they will chirp more.

8. Step 4. Test Your Hypothesis-Experiment
Experiment must be controlled
- tests only one thing at a time
A controlled experiment compares a control group with an experimental group
The control group provides a normal standard against which the biologist can compare results of the experimental group.
The experimental group is identical to the control group except for the one factor being tested
- the variable being tested is the independent variable
Emphasize that there is only one difference between two groups

9. Experimental Design Needs to be repeatable Should test a large sample
Should be without bias

10. Variables Variable = anything that can change in an experiment
Controlled variables = What do I keep the same?
Independent variables = What do I change?
aka Manipulated variables
Dependent variables = What do I measure?
aka Responding variables

11. Cricket Experiment 20 crickets grown in a 10 gallon aquarium
Control Group
Experimental Group
20 crickets grown in a 10 gallon aquarium
12 hours of light/day
Fed 5 g Acme Cricket Food
Kept at 60 degrees F
20 crickets grown in a 10gallon aquarium
12 hours of light/day
Fed 5 g Acme Cricket Food
Kept at 80 degrees F

12. Step 5 Data and Results
Data = observations or measurements - Quantitative = number data 10 chirps/minute - Qualitative = observations color changed to orange Results = Processed data – makes the meaning of the data more clear. Allows you to see trends or patterns. Calculate an average, graph of data etc..

13. Graphing Your Data
Independent Variable- the factor that is changed before the experiment begins. It goes on the x-axis. Sometimes called manipulated
Dependent Variable- the factor that you ran the experiment to measure, sometimes called results. It goes on the y-axis. Sometimes called responding

14. Sample Graph Dependent Variable: on the Y Axis
Independent Variable on the X Axis

15. Conclusions Was your hypothesis correct?
- do the results support your hypothesis
What are possible sources of error?
What next? – What question could you study next?
Why is this important?

16. Repeat Your Work/Publish
Repeat experiment to confirm your results.
When scientists have completed their
work, they publish their results
- this informs other scientists of their
findings

17. Theory
A hypothesis that has been tested repeatedly and shown to be correct becomes a theory
Theories can explain current observations and predicts new observations
A theory is as close to certainty as you get in science

18. Vocabulary to Know and Love
hypothesis
experimental group
control group
variable
controlled variables
independent/manipulated variable
Dependent/responding variable
data
quantitative data
qualitative data
Results
theory