Opener

1. Opener • Imagine that all the birds around the school are dying. How might you investigate the problem? Write a brief description of your investigation. • Which stages of scientific investigation are present within your answer?

2. 1.2 Scientific Methods

3. Why is the geese population boom over? Steps of the scientific method • Making observations • Question • Research/Prior knowledge • Forming a hypothesis • Experiment • Data/Results • Conclusions • Report

4. Making Observations • The act of noting or perceiving objects or events by using the senses • Can be directly or indirectly observed • Begins with an observation that leads to questions

5. Research/Prior Knowledge Research • Look up background information to gain further information about your question • May find the answer to your question Prior knowledge • Relying on what you already know about that topic.

6. Forming a Hypothesis • Possible explanation that can be tested by observation or experimentation. • Attempt to make a connection between an observation and information • Written as an If…then statement • Not a guess!!

7. Scientific Experiments • Procedure that is carried out under controlled condition to test a hypothesis. Controlled • Tests 1 factor at a time and uses a control group • Control group – serves as a standard of comparison because the group receives no experimental treatment

8. Dependent vs Independent Variables • Variable – the 1 factor that is changed w/in the experimental group Independent variable • The single factor that scientists change in an experiment Dependent variable • Factors that may change in response to the independent variable • Typically this is how you going to measure if there was a difference.

9. Study done w/out Experimentation Why? • An experiment is not possible or not ethical • Researchers attempt to find connections in data gathered. • Ex. Dental plaque contributes to heart disease

10. Analyzing Results • Look at the results of the experiment and determine what they are saying. • They be placed in a table, graph or chart to make the results easier to see • My require you to change your hypothesis

11. Draw Conclusions and Report Results • Explains whether or not their hypothesis was correct and why. Report Results • This will allow other scientists to study what you did and repeat the experiment to verify their results.

12. Preventing Bias • Scientists try to prevent bias from affecting their work but bias can still influence an experiment • Sources of funding , personal involvement in an product and other conflicts of interest can affect an experiment

13. Scientific Theories • In science when related hypotheses are well supported and explain a great amount of data, these hypotheses maybe put together to form a theory • The main difference between a theory and a hypothesis is that a hypothesis is a specific testable predication for a limited set of conditions and a theory is a general explanation for a broad range of data

14. Example: Tomatoes • Plant 20 seedlings = 50-60 tomatoes harvested • Plant 20 seedlings w/ fertilizer = >100 tomatoes harvested What can you conclude? What other factors may affect the growth? • weather better that year, different type of tomato seed, fewer pests than last year • Hypothesis • If I use fertilizer then the tomato crop will increases in production

15. Field 1 Brand A tomato seed Water three times a day for 15 minutes Similar type of soil Try to control pests Doesn’t receive fertilizer Field 2 Brand A tomato seed Water three times a day for 15 minutes Similar type of soil Try to control pests Receives fertilizer Experiment

16. Control • the group that is being compared to, normal conditions • Unfertilized tomato plants • Independent variable • the factor the differs among the test groups • fertilizer • Dependent variable • the measurable change that results from changing the independent variable • # of tomatoes yielded • Results • Unfertilized = 55 • Fertilized = 82 • Conclusion • The fertilizer caused an increase in the tomato crop