I. The Nature of Science A. How does science happen? 1. Scientists investigate 2. Scientists plan experiments 3. Scientists observe 4. Scientists always test results
B. Science 1. a system of knowledge based on facts and principles 2. Science has many branches a. biological science – science of living things 1) botany – study of plants 2) zoology – study of animals 3) ecology – balance in nature 4) medicine
b. physical science – science of matter and energy 1) physics – forces and energy 2) chemistry – matter and its changes
c. earth science – science of the earth 1) geology – rocks and minerals – the science of the physical nature and history of the Earth 2) meteorology – atmosphere and weather d. crossover – ie. – biochemistry, geophysics
C. Science and technology work together 1. technology a. the application of science
D. Scientific Theories – Laws – Facts - Hypothesis 1. Fact – in science, an observation that has been repeatedly confirmed a. i.e. objects fall when dropped b. i.e. humans have 46 chromosomes
2. Law a. a descriptive generalization about how some aspect of the natural world behaves under stated circumstances b. i.e. the path of each planet around the sun is an ellipse with the sun at one focus (Kepler’s First Law of Planetary Motion)
3. Hypothesis a. a testable statement about the natural world that can be used to build more complex inferences and explanations b. If…then…
4. Theory a. a broad and comprehensive statement of what is believed to be true, supported by considerable experimental evidence resulting from many tests of related hypotheses
c. Examples of Scientific Theories 1) atomic theory – all matter is made of atoms 2) cell theory – all living things are composed of cells 3) theory of gravitation – all matter attracts other matter 4) theory of plate tectonics – Earth’s crust is made of plates which move over time
5. Theories and laws are not absolute – as we do more experiments and learn more about the world around us, our explanations can change
Why is it important to study science? So we can: 1. 2. 3. 4. 5.
What do we need to know about science? 1. 2. 3. 4. 5.
II. Science Safety A. What are the five most important things to remember about safety in the science laboratory? 1. 2. 3. 4. 5. Prentice Hall Biology. Pearson Prentice Hall. 2002?
III. The Way Science Works ** Critical Thinking – applying logic and reason to observations and conclusions A. Scientific Processes 1. Observing and Collecting Data a. all scientific understanding of the natural world is ultimately based on observations
b. Observing 1) the use of one or more the five senses to perceive objects or events c. Collecting Data 1) the gathering and recording of specific information based on observations
2. Measuring a. the process of determining the dimensions of an object, the # of objects in a group, the duration of an event, or other characteristics in precise units
b. Types of Data 1) quantitative data a) numbers b) ie- 2,457 meters, 87 seeds germinated 2) qualitative data a) descriptive (adjectives) b) ie – a long distance, dark green, plant B is taller than plant A
c. accuracy 1. number that is close to the true value d. precision 1. number that is as exact as possible (ie – 47.452134 cm) Not Accurate Accurate
c. accuracy 1. number that is close to the true value d. precision 1. number that is as exact as possible (ie – 47.452134 cm) Precise Not Accurate Precise Accurate
3. Organizing Data a. involves placing observations and measurements in some kind of logical order – graph, chart, map Prentice Hall Biology. Pearson Prentice Hall. 2002?
4. Classifying a. the process of grouping objects, organisms, or phenomena into an established organizational scheme, or developing new organizational schemes
The Periodic Table PIC of Periodic Table Physical Science – Prentice Hall – Ch. 5 PowerPoint, 2007.
5. Hypothesizing a. the process of forming testable statements about observable phenomena b. hypothesis – testable statement c. a statement is testable if evidence can be collected that either supports the hypothesis or rejects it
D. How to write a Hypothesis 1) the hypothesis must be a complete sentence 2) to the point/concise 3) must try to answer the question/problem 4) must be TESTABLE
5) “IF…THEN…” 6) do not use pronouns (I, we, it, etc.) – BE SPECIFIC 7) “IF (independent variable/cause)…THEN (dependent variable/effect)
6. Predicting a. After making a hypothesis, make a prediction b. Stating in advance the result that will be obtained from testing a hypothesis c. “If…then…”
7. Experimenting a. some hypotheses or predictions can be tested through observations in a natural setting while others cannot b. Experimenting – the process of testing a hypothesis or prediction by carrying out data – gathering procedures under controlled conditions
c. controlled experiments 1) based on a comparison of a control group or phase with an experimental group or phase
2) independent variable a) the manipulated variable – the one that is different 3) dependent variable a) the thing that is different because of the independent variable – usually what is being measured
4) extraneous variables a) factors which may impact the effect on the dependent variable 5) validity a) do the results answer the questions that we are asking in the hypothesis 6) reliability a) will you get the same results if you do these procedures again 7) cause:effect = independent:dependent
8. Analyzing Data a. the process of determining whether data are reliable and whether they support or refute a given prediction or hypothesis
b. ways to analyze data 1) using statistics 2) interpreting graphs 3) determining relationships between variables 4) comparing the data to those obtained from other studies 5) determining possible sources of experimental error
9. Inferring a. the process of drawing conclusions on the basis of facts or premises instead of direct perception b. Facts might include data gathered during a field study or an experiment c. Premises might include conclusions drawn from previous knowledge or from past experience d. some inferences are testable and some are not
Observation vs. Inference StatementObservationInference Object A is round and orange. X Object A is a basketball. X Object C is round, black & white X Object C is larger than Object B X Object B is smooth X X Object B is a table-tennis ball Each object is used in a different sport X X
10. Modeling a. constructing a representation of an object, a system, or a process that helps to show relationships between data b. visual, verbal, mathematical c. model airplane, computer models, experiments in a lab, mathematical equations
11. Communicating a. sharing information 1) to keep from repeating experiments 2) Utilize resources more effectively 3) To keep from repeating failed experiments 4) Swap ideas b. scientific journals, newspapers, magazine, conferences, internet, television news
B. The Scientific Method of Investigation 1. Identify the Problem 2. Review Related Literature 3. Develop a Hypothesis 4. Design the Experiment 5. Conduct the Experiment/ Make Observations 6. Draw Conclusions 7. Communicate the Findings