The Scientific Method Using Plant Experiments to discover the Scientific Method
Plus or Minus Treatment With or without Dose-Response Study Variation in amount Factional Experiment Two variables Comparative Experiment Plant species vary Types of Plant Experiments
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
Using Experimental Design Methods • Brainstorming - Four Question Strategy • Experimental Design Diagrams • Determine Procedure • Conduct Experiment • Record Results • Analysis of Results • Conclusion
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?
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 Variables Independent Variable - change (#3) - limit to one variable - all other variables are constants Dependent Variable - measure (#4) - limit to one variable
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
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.
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.