1. The Science of Biology
Chapter 1

2. Biology is…
Bios – life
-logy – study of
The science that seeks to understand the living world

3. Science is…
an organized way of using evidence to learn about the natural world

4. The goal of science is to…
Investigate and understand the natural world
Explain events in the natural world
Use those explanations to make useful predictions

5. Scientific thinking
Begins with observation
Collecting data
*quantitative *qualitative
Use data to make inferences- logical interpretation based on prior knowledge or experience

6. 1.2 How Scientists Work
Designing an experiment
1. Identify problem
2. Get background info.-Research
3. Form a hypothesis
4. Set up controlled experiment
5. Collect/analyze data
6. Form your conclusion
7. Publish results

7. A proposed scientific explanation for a set of observations
Hypothesis
An educated guess
A proposed scientific explanation for a set of observations

8. Independent Variable Manipulated variable
The one that is changed by the scientist

9. Dependent Variable Responding variable
The one that is observed or measured
Changes in response to the manipulated variable

10. Constant (controls)
The things that you hold constant throughout the experiment

11. What is the effect of temperature on solubility?

12. Review Science is an organized way of using evidence to learn about…
3 goals of science
How do scientists think?
How do scientists work?

13. Think about this question….
Does the amount of sleep a student gets affect how well the student does in school?
Form a hypothesis
Identify the independent variable
Identify the dependent variable
Label the x and y axes of a graph with the correct variables.

14. FLIES on MEAT What was Redi’s hypothesis? (pg.9)
Why did he design an experiment that tested only one variable?

15. Scientists keep written records of their data, observations
Scientists use the data from an experiment to evaluate the hypothesis and draw a valid conclusion
(accept or reject hypothesis)

16. Scientists publish and repeat experiments
Important to write procedure so it can be repeated
Needham and Spallanzani (mid- 1700s)

17. John Needham
Claimed spontaneous generation could occur under right conditions
Heated gravy in sealed container
After a few days found “animalcules”
What did he infer?

18. Lazzaro Spallanzani Needham didn’t heat samples enough
Boiled 2 containers of gravy
Sealed one and left the other open
What do you think happened to the 2 containers of gravy?

19. Sometimes it is not possible to do an experiment
ethical considerations
voluntary human subjects
animal-based research

20. Theory
A well-tested explanation that unifies a broad range of observations
Helps scientists make accurate predictions about new situations
How does a theory compare with a hypothesis?