1. The Scientific Method

2. 1. Steps of the Scientific Method
1. Ask A Question– Determine the question or problem
that is trying to be answered
2. Gather Information - Gather as much information
about the topic as possible
3. Form a Hypothesis – A proposed answer to the
question, written in an if/then format

3. Scientific Method (con’t)
4. Test the Hypothesis – design and carry out an
experiment
A. Independent (manipulated) Variable
B. Dependent (responding) Variable
C. Controlled Variables
5. Record and Analyze Results – Summarize what the
data means
6. Draw a Conclusion – Restate the question and how
you came to the result that you did

4. 2. Scientific Method Example
a. Ask a Question: “What light color will produce the
tallest tomato plant?”
b. Gather Information: Research the purpose of light
in helping a plant grow, how long it takes for a
tomato plant to reach maturity, amount of water,
fertilizers needed, etc.

5. Scientific Method Example (con’t)
c. Form a Hypothesis - IF tomato plants are grown
under a _____ light, THEN they will grow faster
than plants grown under ____, _____,or
_____lights
d. Test the Hypothesis – Design and carry out an
experiment – list the materials and procedure
Materials: Four 5cm tall tomato plants, soil, water, metric ruler,
plant pots, red/green/blue/white lights

6. Scientific Method Example (con’t)
d. Test the hypothesis (con’t)
1. Gather materials
2. Plant each tomato plant in a pot containing the
same amount of soil
3. Measure plants on day 1 as the initial height and
record.
4. Place one plant under red light, one under blue
light , one under green light, and one under white
light.
5. Water plants daily with 50 mL of water
6. Measure plants every third day and record.
7. Compare growth.

7. Identify the following variables in the tomato
experiment
 Independent Variable
 Dependent Variable
 Controlled Variables (3)

8. Scientific Method Example (con’t)
e. Record and Analyze Results
Light Day 1 Day 4 Day 7 Day 10
Color
Red 5.0cm 7.3cm 9.9cm 11.7cm
Blue 5.0cm 7.5cm 10.2cm 12.3cm
White 5.0cm 8.1cm 10.9cm 14.5cm
Green 5.0cm 6cm 6.7cm 7.2cm
In addition to creating a graph, this is also when you would talk
about possible errors in the experiment. List some errors
that you see with this procedure.

9. Scientific Method Example (con’t)
F. Draw a Conclusion – What conclusions can be
drawn from analyzing the data? In other words,
under which light did the tomato plant grow best?
Worst?