1 / 11

scientific method: - PowerPoint PPT Presentation

Scientific Method:. Science is ultimately based on observation (perceiving objects or events using one of the five senses) Observations often lead to questions ---> which lead to experiments to answer the questions.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

PowerPoint Slideshow about 'scientific method:' - ostinmannual

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Scientific Method:

Science is ultimately based on observation (perceiving objects or events using one of the five senses)

The common steps that biologists and other scientists use to gather information and answer questions

• usually begins with scientists identifying a problem to solve by observing the world around them

• 2nd- formulating a hypothesis:

an explanation for a question or a problem that can be formally tested

• A hypothesis is not a random guess.

• A hypothesis can never be proven only shown to be valid; however it can be proven false.

• Examples

• Good

• 1. Plants will grow taller when given Miracle Grow.2. Girls will score higher on math tests than boys.3. Hermit crabs choose colorful shells over drab shells.

• 1. Plants will grow better when given Miracle Grow.2. Girls are smarter than boys.3. Hermit crabs like colorful shells.

• 3rd- design a controlled experiment to test the hypothesis

What is a controlled experiment?

• In a controlled experiment, only one condition is changed at a time.

• All variables are kept constant except the one you are testing

Setting up a test in duplicate- involves two groups: the control group and the experimental group

• The control is the group in which all conditions are kept the same. The control is a “reference point” for comparison

• The experimental group is the test group, in which all conditions are kept the same except for the single condition being tested.

• In a controlled experiment, only one condition is changed at a time.

• The condition in an experiment that is changed is the independent variable

~controlled by the experimenter

• While changing the independent variable, the scientist observes or measures a second condition that results from the change

• This condition is the dependent variable, because any changes in it depend on changes made to the independent variable

• Formulate a PROCEDURE

• Replicate

• Sample size (large enough)

• Collect data

• A scientist carefully collects and organizes data from the experiment. Data should always be presented in a neat fashion, usually tables or graphs.

• Conclusion:

Based on the data, a scientist then determines whether the hypothesis was supported or refuted. Be careful here, scientists usually don't use the word "prove" because there are no absolutes in science. In science, every conclusion must assume that the conclusion is only "true to the best of our knowledge". This is an important distinction between science and other subjects. Science is subject to change when new evidence is found. And while experimentation and observations can provide strong evidence for a conclusion, it is not absolute proof.

Theory settings.

• Theory is an explanation for natural events that is based on a large number of observations.