HOW SCIENTISTS ANSWER QUESTIONS!

Scientific Inquiry

Scientific Inquiry

The many ways that scientists study the natural world and propose explanations based on the evidence they gather

Steps of Inquiry

Step One: Ask a questionQuestion must be testableDoes not involve personal

opinions

Example: Why do flowers have bright colors?

Which of these questions can be answered by inquiry? Is football a better sport then baseball? Does running make your muscles stronger then

swimming? Which brand of running shoes look the best?

Come up with your own “testable” question. It can be about ANYTHING.

Step two: Developing a hypothesis

A possible answer for the question being asked Based on your prior knowledge and

predictions Must be testable!

Can you do an experiment to find out if you are right or wrong?

A hypothesis should be tested many times before it is accepted as true or false

How to write a hypothesis

Sometimes it is written as an “If/Then” statement

Not always possible to write it this way!Question:

Are students more active after eating lunch? I think that if students eat lunch, then they

will be more active Can we test this hypothesis?

Practice:

Does drinking coffee as a teenager make you shorter? Hypothesis:

Step Three: Designing an experiment

HOW will you test your hypothesis?Develop a PROCEDURE

The steps you follow to test your hypothesis and answer the question

How am I going to answer the question? Must be detailed and specific

Things to know when writing a procedure

Variable:Something you change or

manipulate during an experimentExample: You are trying to find

out if a pond plant grows best in clean or dirty water Variable: clean or dirty water

In order to have a successful experiment you must CONTROL the variables that are NOT being tested Keep other variables the same

throughout the whole experiment Example: water temperature, where the water comes from, type of pond plant must be the same for the whole experiment.

Two types of variables:

Manipulated variable :the thing that is purposely changed in an experiment Clean or dirty water

Responding variable: The thing that may change in response to the manipulated variable How well the pond plant grows

Controlled Experiment

Only ONE variable should be tested at a time

Testing more then one variable at a time can confuse the results You can’t test whether pond plants grow

better in clean or dirty water AND whether they like warm or cold water

Variables that you keep the same for the experiment are called controlled variables

Practice

Question: Do worms survive better in wet or dry soil?

Variables: Manipulated: Responding: Other variables to control:

Step Four: Results

The data you collect after performing the experiment Numbers (quantitative observations) Descriptions (qualitative observations) Usually organized into a data table and/or graph

Analyze Results/Conclusion

Interpret your results.Must be based on the

results from your experiment only

States whether your hypothesis was correct and any further testing that needs to be done

Share and Repeat

Scientist must share their results with the scientific community

Repeat – in order to prove a hypothesis you must repeat the same experiment many times.

Types of Experiments

Statistical experimentsControlled/laboratory experimentsField experiments