Unit 1: The Scientific Method Chapter 1-1 & 1-2

What is Science? Science is a method of thinking about the natural world. Biology is the scientific study of life.

Scientific Method The scientific method is a procedure scientists use to seek answers to questions.

THE SCIENTIFIC METHOD PROBLEM HYPOTHESIS EXPERIMENT FORM A NEW HYPOTHESIS REPEAT THE WORK RECORD DATA & ANALYZE RESULTS CONCLUSION ACCEPT HYPOTHESIS REJECT HYPOTHESIS

1. Identify a Problem Observations are descriptions about the way something is or the way things happen From these observations, a question is formed about why or how

Example: Identify a problem Barney observes: When I drink Coke, I burp a lot. He asks Professor Frink: Why does Coke cause burping?

Example: Identify a problem Professor Frink explains: You can do background research to help you know more Look online about the physiology of burping

Wikipedia - not always 100% accurate, but a good start for background information carbon dioxide in drinks causes gas pressure to build in the stomach

2. Create a Hypothesis A Hypothesis is a prediction that may provide an answer to the question The hypothesis must be “testable” The hypothesis must be written in the form of an “If…, then…” statement

Example: Create a Hypothesis If people drink Coke, then they will burp more. Student example(s)…….

Hypothesis vs. Theory Hypothesis: is an educated guess that can be tested and may or may not be true Theory: a well-tested hypothesis that is supported by many types of observations In science, theories are nearly facts Ex. Theory of Evolution, Theory of Relativity, Cell Theory

3. Controlled Experiment Test the hypothesis Procedure—the steps followed during an experiment Well designed experiments have a control group and experimental group(s)

Subject Subjects

Control Group: all variables are kept the same (constant) Used for comparison Experimental Group: all the same variables except the one thing you are testing

The experimental group drink Coke. The control group drink water. Independent Variable Control

Variables: anything that can influence the outcome of the experiment Examples: age of subjects, health of subjects, having food or drinks before the experiment Independent Variable: What you are testing (The variable that is changed) Dependent Variable: what is measured or observed The variable that changes because of the independent variable

Example: Experiment Independent Variable: type of beverage Dependent Variable average number of burps Control Independent Variable

4. Record Data & Analyze Collect & record Data (information) Qualitative data: descriptions Quantitative data: numbers Data can be recorded in a table Analyze the data by graphing it Bar graphs: show comparisons Line graphs: show changes over time

Example: Recording Data Average # of Burps Control Group: Water 2 Experimental Group: Coke 6 Dependent Variable: what you measure Independent Variable Control

Analyze the Results: Bar Graph Proper units Title Average Number of Burps for Water vs. Coke Y-axis = Dependent Variable Type of Beverage X-axis = Independent Variable Label

5. Conclusions The results tell whether the hypothesis was “accepted or rejected”

Example: Conclusion Accept or reject the hypothesis? Why? ACCEPT! There were more burps with Coke than with water based on the data and the results of the graph.

6. Repeat the Work When a hypothesis is supported by data from additional investigations, it is considered valid. When a hypothesis is not supported, it means that we need to go back and ask new questions or identify sources of error in the experiment.

THE SCIENTIFIC METHOD FORM A NEW HYPOTHESIS REPEAT THE WORK ACCEPT HYPOTHESIS REJECT HYPOTHESIS

THE SCIENTIFIC METHOD PROBLEM HYPOTHESIS EXPERIMENT FORM A NEW HYPOTHESIS REPEAT THE WORK RECORD DATA & ANALYZE RESULTS CONCLUSION ACCEPT HYPOTHESIS REJECT HYPOTHESIS