BIOL 109N 1st Edition Lecture 2Outline of Last Lecture I. What is LIFE? II.7 Characteristics of LIFE III.Biological Diversity-Levels of organizations of life. Outline of Current Lecture I. What is SCIENCE? A. Definition of scienceII. Scientific MethodIII. Steps of Scientific MethodIV. Scientific Method- How it works- Set-Up ExperimentV. Basic terminology Current LectureI. Science is a way of knowing. By nature humans are very curious. Science allows us to askquestions, observe the natural world. Definition of science is a systematic approach to answering questions. Science uses observation and experimentation to describe and understand why things happen as they do in the natural world. Science is perceived by senses, repeatable by others, interpreted according to specific rules. II. Scientific Method is a way of learning about the natural world by applying certain rulesof logic to the way information is gathered and conclusions are drawn. Each science has specific steps to answer questionsIII. Steps of Scientific Method: 1. Make observation. Make careful observation and ask questions: What? Why?When? How?. By observing something we often can come up with some solution. 2. Develop testable hypothesis. Your hypothesis is just your question or problem in the form of a statement. Develop hypothesis using:- Prior knowledge- Additional observationsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Rules: mechanistic- experimental, clear, as simple as possible and testable& falsifiable. Hypothesis: a statement that tries to explain the question; NEVER can be proven true. Example: Adding fertilizer will make plants grow taller.3. Test hypothesisa) Make predictions = specific statements that can be directly tested.IF …… then statement: If the hypothesis is correct THEN I should observe……b) Test predictions: If predictions met, hypothesis supported. If predictions not met, hypothesis is proven wrong. Note: the hypothesis can be supported but cannot be proven to be correct. Prediction: If fertilizer is added then plants will grow taller. Experimental Questions: Does one variable affect another variable?Is there a relationship between one variableand another? Variable is something that is changed or can be varied in the experiment. Example: temperature, length of day, number of ants, amount of light, color. Example: There is a relationship between the amount of fertilizer and the height of the plant. (variables highlighted and underlined in red) The results either support of reject the hypothesis. 4. Draw a conclusion. The results either support of reject the hypothesis. IV. Scientific Methods: - How it works: Oatmeal helps remove cholesterol! 1) Observations: High levels of cholesterol are fatty deposits which clog blood vessels which then leads to atherosclerosis or heart attack. Oatmeal contains the soluble fiber B-glucan, which binds to bile preventing it from being reabsorbed into the body. Bile is high in cholesterol therefore bile bound to soluble fiber is removed from the body= the liver then removes cholesterol from blood.2) Set up Experiment : Decrease variability among test subjects: All test subjects, even control must have similar cholesterol levels to start with: same gender, age, dietary habits. - Hypothesis: eating oatmeal will lower cholesterol - Prediction: if oatmeal consumption lowers blood cholesterol levels, than person’s cholesterol will be lowered by eating a bowl of oatmeal a day for 6 weeks. - Perform experimentGroup 11 oz. ofoatmeal/perdayGroup 22 oz. ofoatmeal/per dayGroup 33 oz. ofoatmeal /perdayControlgroup1 oz. offarina/ per day- Independent variable – amount of B-glucan (soluble fiber) consumed over time/ dependent variable – level of cholesterol in the blood. - Conclusion – Eating oatmeal lowers blood LDL cholesterol. - Experimental test results can be used to revise hypothesis and explain the observable world more accurately: try to further refine a hypothesis, make new and more specific testable predications. IV. Basic terminology- Variable: a condition that can change- Independent variable: can be manipulated - Dependent variable: depends on the independent variable - Controlled experiment: the effects of al variables are controlled. Except for the independent variable whose effects is being tested- Control: an unmanipulated point of comparison- Quantitative data: uses numbers- Qualitative data: does not use