1. The Science of Biology Chapter 2

2. What is Science??  Science (“to know”) is a way to ask questions about the natural world  Science is testable or falsifiable; beliefs, opinions, and the supernatural are not testable  Science is supported with evidence that can be verified through repeated experiments

3. What is Science?? (continued)  Science is NOT a set of unchanging facts; it is an ongoing process that advances knowledge and understanding  Scientific knowledge is uncertain  Reality is complex  Explanations of reality are not absolutely true  Allows for alternative explanations to better explain observations  Scientists must be skeptical (question existing ideas) and open-minded (consider new hypotheses if the data supports it)

4. Discovery Science  Describes natural structures or processes through careful observation and data collection  Emphasizes inquiry and observation  Inquiry is about asking questions based on observations and actively seeking answers  Observation is the use of the senses or instruments to gather and record information about structures or processes  Observations are recorded as Data

5. Types of Data QUANTITATIVE  A recorded measurement  Scientists worldwide use the metric system QUALITATIVE  Descriptions, drawings, or photographs  Best data is documented, clearly organized, consistently recorded, and reliable

6. Inferences  Logical conclusions based on observations  Example: In 1928, Alexander Fleming observed a mold contaminating a cultured of bacteria. He noticed no bacteria growing near the mold. He inferred that the mold was killing the bacteria.

7. Practice making Inferences…

8. Inferences and Generalizations in Science  Inferences help refine general questions into specific questions that can be explored further Ex: What substance produced by this mold is killing the bacteria?  Generalizations are conclusions formed from many specific observations that are related Ex: Many molds have antibiotic properties that can be used to kill bacteria harmful to humans.

9. Hypothesis-based Science  Seeks explanations to specific questions by testing predictions Ex: Poisonous snakes have bright colors and rings. Some non-poisonous snakes also have bright colors and rings. Question: What is the function of such mimicry? POISONOUS NON-POISONOUS

10. Form a Hypothesis Hypothesis: Mimics benefit because predators confuse them with the harmful species. Restate the hypothesis in “IF, AND, and THEN” format: If this idea is true, and I do this, then this will happen. EX: If predators confuse the mimics with the harmful species, and I expose predators to non-poisonous snakes with rings and without rings, then the predators will attack the species without the rings more often.

11. Design a Controlled Experiment  The experiment is designed to test the hypothesis  Can only test the effect of ONE variable!! Ex: The presence of colored rings on the snakes body The Control GroupThe Experimental Group

12. Organize Data and Interpret Results  Quantitative data should be organized into charts and graphs  The results will either support the hypothesis or cause the scientist to revise his or her hypothesis and test again

13. Theories in Science A theory is a well-tested explanation that makes sense out of a great variety of scientific observations  Supported by an extensive body of evidence  Provide framework for future research and predictions  Subject to modification as new evidence is uncovered

14. Models in Science  Models are physical, mental, or mathematical representations of how to understand a process or an idea  Can be drawings, graphs, 3D, computer programs, or equations

15. Communication and Technology in Science  Communication is necessary for cooperation and competition among scientists  Scientist communicate their ideas in published journals and the web  Technology is the result of applied scientific understanding Ex: Structure of DNA = Science Genetic Engineering = Technology

16. Science, Technology, and Society  Technology is not driven by the curiosity that drives basic science, but by the needs and wants of humans  Ethics in Science: Debated issues about technology ask “should it be done,” not “can it be done”  Good citizens make an effort to understand the technology before making lifestyle and democratic choices