Scientific Method

Scientific Method The scientific method is the procedure consisting of systematic observation, measurement, experimentation, and the formation and testing of a hypothesis.

1. Observing Observation is taking notice of a problem or unusual event. Ex. In 1976 , a deadly pathogen (Ebola) appeared in the Congo. The doctors observed symptoms and the locations of cases of this pathogen to determine the cause and how it was spread.

2. Asking a Question All investigations begin with question in order to determine what needs to be investigated further. Ex. Ex. How was the disease transmitted? What is the disease causing agent?

3. Hypothesizing The hypothesis is the suggested explanation or prediction for an observation or question. The hypothesis is worded as a statement that is testable. The hypothesis should be stated in the ”If…then…” format. The hypothesis can be supported or rejected by data. It can NEVER be proven! A prediction is stating the results of the hypothesis. Ex. If the virus were the true disease causing agent, then introducing the virus into healthy tissue would cause cell death.

4. Collecting Data Collecting data is the longest phase of the scientific investigation. The data is all of the information gathered to answer the hypothesis. Collecting data has four main requirements such as observing, measuring, sampling, and organization. Observing is qualitative data with the recording of unusual events that raise questions. Measuring is quantitative data dealing with all of the numbers. Sampling represents using a large and random sample to represent the entire population. Organization is used to organize the collected data into charts, tables, and graphs.

How does ____IV____ affect ____DV___? 5. Experimenting Experiments are designed to test a hypothesis by gathering data in controlled conditions. There are many aspects to take note of when conducting an experiment. Every experiment must have: A control group that serves as a standard of comparison with another group; this group is not subjected to what is tested. An experimental group serves as the group that is subjected to what is tested. An independent variable that is the one thing that is different between the two groups. A dependent variable that is the measured results of the experiment. All data is analyzed in respect to the hypothesis. How does ____IV____ affect ____DV___?

5. Experimenting Example: Group A kidney cells exposed to infected blood Group B kidney cells not exposed to infected blood Scientists observed cells’ health over many days Group A kidney cells died What is the independent Variable? What is the dependent variable? What is the control group? What is the experimental group?

6. Drawing Conclusions Conclusions are drawn from the collected data and can be expressed through modeling, inferring, and forming a theory. Modeling is the explanation of the conclusion supported by the data. Inferring is the conclusion made based on raw data. Forming a theory is the comprehensive statement of what is thought to be true. Ex. The Ebola fever is a virus that was transmitted with close contact with infected victim.

Report Findings! After drawing your conclusions, report your findings! Your findings can be reported in a lab report, journal article, announced on the media, or published in a book.