The Scientific MethodThe Scientific Method
Using Plant Experiments to discover the Scientific Method
Types of Plant ExperimentsTypes 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
Using the Scientific Inquiry MethodUsing 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
Using Experimental Design MethodsUsing Experimental Design Methods
• Brainstorming - Four Question Strategy
• Experimental Design Diagrams
• Determine Procedure
• Conduct Experiment
• Record Results
• Analysis of Results
• Conclusion
Four Question StrategyFour 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?
What materials are readily available for conducting experiments on PLANTS?
Plants
Soil
Fertilizers
Water
Light
Containers
How do PLANTS act?
Grow
Reproduce
Produce oxygen
Produce sugar
Produce fruit
How can I change a set of PLANT materials to affect the action?
Plants
Soil
Fertilizers
Water
Light
Containers
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
Select VariablesSelect Variables
Independent Variable - change (#3)
- limit to one variable
- all other variables are constants
Dependent Variable - measure (#4)
- limit to one variable
Experimental Design DiagramExperimental Design DiagramTitle: 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
Example IExample 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.
No Fertilizer 5% Fertilizer 10% Fertilizer 15% Fertilizer
15 plants 15 plants 15 plants 15 plants
Independent Variable:
Dependent Variable:
Height of Bean Plants in Centimeters
Constants:
Amount of water, light, soil, temperature, humidity, etc.