Scientific Inquiry & Experimental Design How do we solve problems in science?

The scientific method… State the problem Form a hypothesis Procedure Results Conclusion Let’s have a more in depth look at what scientist actually use and more scientific terminology.

Experimental Design vs. Scientific Method Research Question Formulating Hypothesis Careful Observation Data Gathering Analysis of Data Identifying patterns in the data State the problem Form a hypothesis Procedure Results Conclusion

Types of Experimental Design Different research questions require different experimental designs. Descriptive Investigations Comparative Investigations Experimental Research Design

Descriptive Investigations An investigation used to explore questions in environmental conditions you cannot control. Ex. Jane Goodall’s study of chimpanzees. Picture hyperlinked to: www.janegoodall.org/media/videos A hypothesis is not required in these investigations.

Comparative Investigations Involves collecting data on different organisms/objects/features, or collecting data under different conditions to make a comparison. Example: times of year, temperatures, locations Hypothesis: Pecan trees produce more pecans during the rainy season than they do during a drought.

Experimental Research Design Can be used when focused on a single variable. Conditions can be controlled. Determines the cause of a problem. Ex.: Thumb Wars

What is a Variable? Any part of an experiment that can change. Independent variable  changed by the “scientist” Dependent variable  changed “because” of the independent variable.

What is a Control? Part of the experiment that is not being tested. Used for comparison. “Keep it fair”  keep all things the same except for one factor.

If a plant is given milk, Then it will die, Because plants need water to survive. Independent variable  Dependent variable 

What happens to your grades if you don’t study? then your grades will decline because you are not prepared for class.

What happens to your heart rate if you do jumping jacks? then your heart rate will increase because your body is pumping more blood.

What happens if you work more hours? then you will make more money because you are paid per hour.

What happens if you brush your teeth? then _______________________ because ____________________.

How does your tan change if you stay outside longer? then _______________________ because ____________________.

Experimental Research Design: Thumb Wars Research Question Hypothesis Gathering Data Data Analysis Patterns in the data One variable tested: thumb length

Experimental Research Design Research Question: Do plants grow better in coke or water?

Do plants grow better in coke or water? Research Question: Do plants grow better in coke or water? Hypothesis Ex: Plants will grow better in water because plants need water to live. Gathering Data: Controlled experiment with one independent variable. Independent Variable: Type of liquid given to plants Dependent Variable: Measured growth of each plant Constants: Conditions kept the same (such as amount of liquid, type of plant, soil, amount of sunlight)

Do plants grow better in coke or water? (cont.) Analysis of Data : Using graphs/tables to find trends in the data.