1. Scientist think and talk
Language of Science
* Are you hyperactive or hypoactive today?
Thinking about thinking
What are the numbers on the bottom of the dice?
How do you know?

2. Scientific Method & Experimental Design

3. Solving Problems
To answer questions scientists use an organized system called the Scientific Method:
Some questions are solved quickly
Some over years
Some never get solved

4. Basic SM
Question
Test
Analyze
Conclude

5. Steps of the Method State a problem
Gather information (research, observations)
Form a hypothesis
Perform an experiment to test the hypothesis
Record & analyze data
State a conclusion
Repeat the work

6. Creating a Hypothesis Based on a small amount of information
An If – Then -- Because statement
Needs to be testable
Needed for experimentation

7. Make a hypothesis
You notice that your scores on your tests in biology over the past month. You want to improve your test scores.
Form a hypothesis:

8. Where to Start
To get precise results that are accepted by other scientists, you need:
a specific hypothesis
design a specific experiment

9. Parts of an experiment In an experiment there are two variables
Independent variable
Dependent variable

10. Independent variables
This is the part of the experiment that is deliberately changed from the beginning of the experiment
The factor that is being tested

11. Trials & Sample Size Set up multiple trials based on the IV
Everything is the same except the factor being tested
Make sure to test more than 1 per trial
Why?

12. Dependent variable This is the part of the experiment that is measured
This measurement tells the scientists if the independent variable has an effect on the outcome of the experiment
2 kinds:
Quantitative & Qualitative

13. Designing of Experiment
In addition to the variables some experiments allow for a control
An experiment where there is not IV

14. The Control
Makes sure that the experiment tests the independent variable
How?
Hold all factors at “normal”
Used for comparison

15. The Results
Results either support or disprove the hypothesis

16. Scientific Hypothesis
A possible explanation for an observation based on a small amount of information

17. Scientific Law
A basic principle that describes behavior of a natural phenomenon. A rule of nature. Explains what will happen.

18. Scientific Theory
A well tested explanation, supported by an overwhelming amount of evidence & is accepted by the majority of scientists. Explains Why
Often used to explain scientific laws

19. Practice your skills
Identify the various elements of scientific method
AND
Identify experimental errors

20. Scenario 1 Compost and Bean Plants
Different aged grass compost on bean plant growth
Older compost should produce taller bean plants
3 flats (25 plants per flat): Flat A given 6 month old compost, Flat B given 3 month old compost and Flat C no compost
Plant height recorded after 30 days

21. Scenario 2 Metals and Rusting
Utilities company burying lead next to iron pipes to prevent rusting
Perhaps more active metals will be better at preventing rusting
Placed following into separate beakers of water: a) 1 iron nail b) 1 iron nail wrapped in aluminum c) 1 iron nail wrapped in magnesium d) 1 iron nail wrapped in lead
Same amount of water used in each and at end of 5 days rated amount of rust

22. Scenario 3
Certain perfume esters agitate bees, wanted to know if Ester X was present in 4 different perfumes by observing bee behavior
Placed 10 mL of first perfume 30 m from hive, recorded time for bees to emerge and behavior
Allowed for 30 min recovery then repeated with additional perfumes

23. Scenario 4 Fossils and Cliff Depth
Observed that different types and amounts of fossils were present in a cliff behind home
Marked bank at five positions: 5, 10, 15, 20 and 25 m from surface
She removed 1 bucket of soil from each of the positions and determined kind and number of fossils in each sample

24. Scenario 5 Aloe vera and Planaria
Aloe vera is to promote healing of burned tissue so it might help with regeneration of planaria.
Bisected planaria to obtain 10 parts (5 heads and 5 tails)
Applied 0%, 10%, 20%, 30%of aloe vera to the groups
15 mL of solutions were applied. All planaria kept in same chamber with same temp, food, etc
On day 15 Jackie observed the regeneration and categorized as full, partial or whole

25. Scientific Theory
A well tested explanation, supported by an overwhelming amount of evidence & is accepted by the majority of scientists. Explains Why
Often used to explain scientific laws

27. SCIENTIFIC METHOD and the Snowshoe Hare
Observations –
Problems (?)-
Hypothesis –
Manipulated (Independent) Variable –
Responding (Dependent) Variable –
Control Group
Constants