The Scientific Method

1
The Scientific Method

• Using Plant Experiments to discover the
  Scientific Method

2
Types of Plant Experiments

• Plus or Minus Treatment
• With or without
• Dose-Response Study
• Variation in amount
• Factional Experiment
• Two variables
• Comparative Experiment
• Plant species vary

3
Using the Scientific Inquiry Method

• Plant a Question
• Sprout a Guess
• Design a Growing Experiment
• Identify independent variable
• Identify dependent variable
• Record Fruitful Observations
• Harvest Conclusions

4
Using Experimental Design Methods

• Brainstorming - Four Question Strategy
• Experimental Design Diagrams
• Determine Procedure
• Conduct Experiment
• Record Results
• Analysis of Results
• Conclusion

5
Four Question Strategy

• 1) What materials are readily available for
  conducting experiments on ?
• 2) How do act?
• 3) How can I change a set of _
  materials to affect the action?
• 4) How can I measure how ______ respond to the
  change?

6

• What materials are readily available for
  conducting experiments on PLANTS?

Plants Soil Fertilizers Water Light Containers
7

• How do PLANTS act?

Grow Reproduce Produce oxygen Produce
sugar Produce fruit
8

• How can I change a set of PLANT materials to
  affect the action?

Plants Soil Fertilizers Water Light Containers
9

• How can I measure how PLANTS respond to the
  change?

- Count the number of leaves - Measure stem
length - Determine growth rate - Count the number
of flowers - Mass of fruit produced - Measure the
diameter of the stems - Measure chlorophyll
absorption
10
Select Variables

• Independent Variable - change (3)
• - limit to one variable
• - all other variables are constants
• Dependent Variable - measure (4)
• - limit to one variable

11
Experimental Design Diagram

• Title The effect of (IV) on the (DV).
• Hypothesis If (IV), then the (DV), will . . .
• Independent Variable
• Dependent Variable
• Constants

Control Variation I Variation II Variation III
of Trials of Trials of Trials of Trials
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Example I

• Title The effect of the amount of fertilizer on
• the height of bean plants.
• Hypothesis If different amounts of fertilizer
  is applied, then the bean plants will vary in
  height.

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Independent Variable
No Fertilizer 5 Fertilizer 10 Fertilizer 15
Fertilizer
15 plants 15 plants 15 plants 15 plants
Dependent Variable Height of Bean Plants in
Centimeters
Constants Amount of water, light, soil,
temperature, humidity, etc.