2 SCIENTIFIC METHOD AND EVALUATING RESOURCES
Learning Objectives
- Test predictions from scientific hypotheses using basic biological laboratory techniques.
- Evaluate publicly-accessible resources.
Activity
- When doing an experiment, why is it beneficial to alter only one experimental condition at a time? Consider the role of independent and dependent variables.
- How can you ensure that your experiment results aren’t influenced by any outside conditions?
- Discuss the answers to questions 1 and 2 with the class or your group.
Scientific Method
Safety Precautions
- Inform your professor immediately of any broken glassware, as it could cause injuries
- Clean up any spilled fluids to prevent other people from slipping
- Wash your hands with soap and water after completion of the activity
For this activity, you will need the following items:
- Water
- Sugar or salt
- Beakers
- Hot plate
- Thermometer
- Reaction time rulers (optional)
- Pillbugs (optional)
- Food sources (optional)
Structured Inquiry
Step 1: Examine the materials available in the lab. Think of a question you could examine about the available materials (e.g., does sugar dissolve faster in warm water than in ice-cold water). Formulate a clear, specific hypothesis you can test during the lab period. Record your hypothesis.
Step 2: Design an experiment to test your hypothesis. Set up a data table on your lab paper to record your data. Write out the steps of your experiment and devise positive and negative controls. Discuss your plan with your professor before proceeding.
Step 3:After your professor approves, execute your experiment and record the data in your data table.
Step 4: Does your data support your hypothesis? Why or why not? What methods could you use to improve your results? Discuss with your lab partner, and then write your answers.
Guided Inquiry
Step 1: Redesign the experiment you previously performed in the Structured Inquiry. Create a more specific hypothesis or create a follow-up hypothesis that you can test based on the results.
Step 2: Create a plan for your experiment, including controls and data tables. As before, your professor should approve your plan before you start your experiment.
Step 3: After your professor approves, execute your experiment and record the data in your data table.
Step 4: Does your data support your hypothesis? Why or why not? How did you improve your experiment over what you did in the Structured Inquiry? How could you further improve your results? Discuss with your partner, and then write your answers on your paper.
Assessment
- What is the purpose of the scientific method?
- You observe that plants sitting in one location in your house grow faster than plants sitting in another location. Create a testable hypothesis to test why this occurs. Then, describe an experiment that would test your hypothesis that includes controls.
Evaluating Resources
It’s important you have the ability to locate reliable information. This activity is aimed to help you critically think about how to evaluate resources and to classify the three types of science articles.
When listening to a person tell a story or reading one yourself, how do you determine if the information is credible?
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How Do You Know a Source Is Credible?
The definition of a credible source can change depending on the discipline, but in general, for academic writing, a credible source is one that is unbiased and is backed up with evidence.
Expectations for Science Source Materials
Different disciplines can have different expectations for sources of information. In a business class, it might be acceptable to use a company website, but that probably wouldn’t work in a psychology class. Science has specific standards, too. Typically, science classifies sources as one of three categories:
- Peer-reviewed/primary source – Data is published in a scientific, professional journal. The information was rigorously tested and has been evaluated by other researchers in the field for accuracy, objectivity, and validity before being published. This is the method used when scientists are sharing information and current research with others within the scientific community.
- Secondary source – Information is provided as a summary of the data published in primary sources. The goal is to convey information on current research findings to the general public. This method is equivalent to reporting science news in a reliable, unbiased platform that is easier to read than primary sources.
- Opinion/advertisement – These resources express ideas based on opinion rather than scientific data. The ideas expressed could be, but aren’t necessarily, accurate according to current research. The tone of the article is biased and/or persuasive.
Assessment
- Use what you know about evaluating source material provided by your instructor to make sure you understand the similarities and differences between these types of science sources.
- Discuss with your group some strengths and weaknesses of the peer-review process.
- What happens when researchers violate principles of integrity? Travel here (or search using ori hhs) to explore Case Summaries from the Office of Research Integrity. Choose one case from the list and click the link. Read over the information, you may not understand all of the content, but look for verbs you do understand. Discuss what you find with your group.
The Evaluating Resources section of this chapter is adapted from Research and Evaluating Sources Lab by Dr. Ephanie DeBey and Jennifer Hulsey Campbell, licensed CC BY-NC-SA 4.0. from Biology Lab Manual for Non-Majors by Tulsa Community College, Licensed CC BY
the variable that is manipulated or changed by the experimenter in a scientific experiment
the variable that is measured in an experiment and is expected to change in response to the manipulation of the independent variable; essentially, it is the variable that "depends" on the independent variable
suggested explanation for an observation, which one can test
