1. The Science of Biology Ch 2

2. I. Science is Based on Inquiry and Observations Science = A way to answer questions about the natural world Starts with asking questions and making observations Uses the scientific method

3. II. The Scientific Method Observing and asking questions →make inference→ hypothesis → experiment→ analysis→ conclusion

4. Observation : – act of noticing things in nature Ex: many nonpoisonous snakes mimic the bright coloration of poisonous snakes

5. Question: based on observations Why do nonpoisonous snakes mimic poisonous ones?

6. Inference: – logical interpretation of the question Mimicry protects the nonpoisonous snakes

7. Hypothesis: – Educated guess or possible answer to a question. Based on observation. Has not been tested yet. If mimicry protects the snakes, then fewer colorful nonpoisonous snakes will be attacked than noncolorful nonpoisonous snakes

8. Experiment – Designed to test hypothesis – A controlled experiment has only one variable being tested or manipulated, the independent variable

9. Independent variable: the variable that you are changing Dependent variable is what is being measured or observed (the effect) all other variables in the experiment should be kept unchanged.

10. Some experiments have a positive control and a negative control – Positive control: – Negative control:

11. Analysis of data: record of observations Tables Graphs Written observations Drawings

12. Conclusions Summarizing the data collected Prove or disprove hypothesis If hypothesis is disproved did experiment fail?

13. Theory: A hypothesis tested MANY times and proven true. However it could eventually be proven false Law: a hypothesis that can NEVER be proven false