1. The Scientific Method
Ms. Cuthrell
Ecology
3rd Period

2. Scientific Method Problem/Question Observation/Research
Formulate a Hypothesis
Experiment
Collect and Analyze Results
Conclusion
Communicate the Results

3. Steps of the Scientific Method
1. Problem/Question: Develop a question or problem that can be solved through experimentation.
2. Observation/Research: Make observations and research your topic of interest.
3. Formulate a Hypothesis: Predict a possible answer to the problem or question.
Example: If soil temperatures rise, then plant growth will increase.

4. Steps of the Scientific Method
4. Experiment: Develop and follow a procedure.
Include a detailed materials list.
The outcome must be measurable (quantifiable).
5. Collect and Analyze Results: Modify the procedure if needed.
Confirm the results by retesting.
Include tables, graphs, and photographs.

5. Steps of the Scientific Method
6. Conclusion: Include a statement that accepts or rejects the hypothesis.
Make recommendations for further study and possible improvements to the procedure.
7. Communicate the Results: Be prepared to present the project to an audience.
Expect questions from the audience.

6. Steps of the Scientific Method
Let’s see what you remember!
What is a hypothesis?
What does quantifiable mean?
What are 3 ways to collect and analyze information?

7. Steps of the Scientific Method
Let’s put our knowledge of the Scientific Method to a realistic example that includes some of the terms you’ll be needing to use and understand.

8. Problem/ Question Tim gets a new fish tank and sets it up in his room.
After he gets the tank ready, he buys a goldfish to try out the tank.
Everything seems fine until he feeds the fish.
After feeding the fish twice, the fish belly-ups in the water and is dead.
The water in the tank is tested and there seems to be nothing wrong with chemical levels in the tank.

9. WHAT IS TIM’S PROBLEM OR QUESTION GOING TO BE?
Problem/ Question
WHAT IS TIM’S PROBLEM OR QUESTION GOING TO BE?

10. Warning!!! Be careful how you use effect and affect.
Effect is usually a noun and affect, a verb.
“ The effect of the amount of food on the goldfish.”
“How does amount of food affect the goldfish’s health?”

11. Observation/ Research
Tim collects information about goldfish from many different sources.
He asks experts at the local pet store, as well as, experts found at his local aquarium.
Tim observes the fish tanks at the pet store, as well as at the aquarium, and write down what he sees.
Tim talks to his teacher and she gives him an experimental design diagram.

12. Experimental Design Diagram

13. Formulating a Hypothesis
After more research and talking with his Ecology teacher, Tim comes up with a hypothesis:
“If the goldfish is given too much food, then it will die.”
Remember: The hypothesis is an educated guess about the relationship between the independent and dependent variables.
Note: These variables will be defined in the next few slides

14. Defining Variables
The independent, or manipulated variable, is a factor that’s intentionally varied by the experimenter.
Tim is going to use 25mg, 50mg., 100mg., 250mg., 500mg. of fish food in his experiment.
The dependent, or responding variable, is the factor that may change as a result of changes made in the independent variable.
In this case, it would be the lifespan of the goldfish.

15. Experiment
Tim’s Ecology teacher helps him come up with a procedure and list of needed materials.
She discusses with Tim how to determine the control group.
In a scientific experiment, the control is the group that serves as the standard of comparison.
The control group may be a “no treatment" or an “experimenter selected” group.

16. What did you learn?
What is the factor called that is changed during an experiment?
What is the factor called that responds to changing parts of the experiment?
What is the factor called that is not changed and is used as a standard of comparison?
Why do you think a control group is important?

17. Experiment
Tim writes out his procedure for his experiment along with a materials list in his journal. He has both of these checked by his teacher where she checks for any safety concerns.
Trials refer to replicate groups that are exposed to the same conditions in an experiment.
Tim is going to test each fish food variable 3 times.

18. Collect and Analyze Results
Tim comes up with a table he can use to record his data.
Tim gets all his materials together and carries out his experiment.
Tim also learned from the expert at the pet store that one goldfish should have about 100 mg of fish food a day, so he will use that group as his control.

19. Collect and Analyze Results
Lifespan of Goldfish (each goldfish in a different bowl)
Trials
Amount of food given
Fish 1
Fish 2
Fish 3
Average Lifespan (days)
25 mg 3 4 2
50 mg 7 5
100mg
(Control) 25 36 29 30
250 mg 15 10 12
500mg 1

20. Collect and Analyze Results
Tim examines his data and notices that his control worked the best in this experiment.
Should Tim reject his hypothesis?
(Meaning it was incorrect)
How could Tim change his hypothesis to be more correct?
“If the goldfish is given too much food, then it will die.”

21. Conclusion Tim changes his hypothesis to:
“If the goldfish is given 100mg of food each day, then it will live the longest.”
Tim then uses this information to write a paper for his class, which he puts in scientific form.

22. Communicate Results
Tim shares his findings with his Ecology class and presents his information at the local Science Fair.
Tim is asked many questions about his experiment and since he has now become an expert, he is able to answer all questions asked correctly.