1. Chapter 1The Science of Biology Section 1:1 What is Science?

3. I. Science goals • A. Investigating and understanding the natural world in an organized way. • Science uses evidence from testing, collecting, organizing, connecting, collaborating, sharing, observing and examining, to learn about the natural world.

4. II. Thinking like a scientist • Scientist usually gather information during experiments or in research in a very organized way. • 1. Data- Recording and gathering information in 2 different ways. • A. Quantitative – data expressed in numbers, obtained by counting and measuring • B. Qualitative – descriptive, involves characteristics that usually cannot be counted.

5. Inference • A logical interpretation based on prior knowledge or experience. It’s like an assumption of what you think. (testing a body of water) • Example: The researcher is test a body of water. The researcher cannot test all the water, so she collects water samples from several different parts of the reservoir. • If all the samples are clear to drink the researcher may infer that the water is safe to drink.

6. 3. Explaining and interpreting evidence. • After a scientist’s initial observation, they will propose one or more hypothesis. • Hypothesis- a proposed scientific explanation for a set of observation, that must be propose so that it can be tested. (educated guess) • Generate this by using: • A. Prior knowledge ( already know) • B. Logical inference • C. Informed, creative imagination

7. Science: as a way of knowing • Science is an ongoing process that is constantly changing. • Scientist are skeptics, questioning existing ideas and new hypothesis. • Scientific way is to view that the whole physical universe is a system or a collection of parts and processes that interact. • Biologist concentrate on the living systems, from invisibly small to the size of an entire planet.

8. Chapter 1 • Section 1:2

9. Section 1-2 How Scientists Work • I. Designing an experiment • 1. Ask a question/problem? Where did life come from? • 2. Forming a hypothesis: Where does life come from? • 3. Design an experiment so you can test your hypothesis. • 4. During the experiment, record your observations, data gathering. • 5. Based on the data you gathered, you are to come to a conclusion.

10. Spontaneous Generation • For centuries people accepted the prevailing explanation for sudden appearance of some life forms. • These living organisms somehow arose from non-living materials. • Mice arose from rice containers • Earthworms appeared on the ground after rain fall. • Maggots appeared on meat over night. • Beetles appeared on dung.

11. Redi’s experiment on Spontaneous Generation, Where do maggots really come from?

12. . • So in Redi’s experiment he was able to prove that keeping flies away from meat would prevent the appearance of maggots. • So by doing the experiment he was able to test his hypothesis and prove that living things do come from other living things.

13. Setting up a Controlled Experiment: This type of experiment uses variables and only one variable can change. All others should be kept unchanged or CONTROLLED. Changing only one at a time…..

14. Variables – factor that can change in an experiment (examples) • Equipment, material, amount of material, temperature, light and time.

15. There are 2 types of Variables • Manipulated variable – (Independent)- the variable that is deliberately changed. b. Responding variable – (Dependent) - the variable that is observed and changes in response to the manipulated variable.

16. So in Redi’s experiment: • the manipulated variable would be, whether or not there was gauze over each jar. • The responding variable would be whether the maggots appeared.

17. D. Recording and Analyzing Results - Testing • Keeping records of all the observations and data during the experiment. • This is more accurate than a verbal explanation.

18. Drawing a Conclusion • Use the data, evidence from the experiment to evaluate the hypothesis, and draw a valid conclusion. • This way they can determine whether the hypothesis is supported or refuted.

19. III. How a Theory Develops A. A well tested explanations and observations that are thought to be true, but could change. Law never changes…..