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Scientific Method (Inquiry). What is the scientific method…. ?. process. The scientific method is a ______ for answering questions. What is Science? or . True. False. Here are a few statements to test your current understanding of science!.
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What is the scientific method….. ? process The scientific method is a ______for answering questions.
What is Science? or True False Here are a few statements to test your current understanding of science!
Science can prove anything, solve any problem or answer any question. True or False? False Science actually attempts to disprove ideas (hypotheses). Science is limited strictly to solving problems about the physical and natural world.
Any study done carefully and based on observation is scientific. False • Science must follow certain rules. The rules of science make the scientific process as objective as is possible. Objective= Not influenced by feelings, interests and prejudices; UNBIASED vs. Subjective= Influenced by feelings, interests and prejudices; BIASED
Different scientists may get different solutions to the same problem. False True True
Understanding Experimental Design A process of discovery…
The Controversy Over Spontaneous Generation Question: What causes tiny living things to appear in decaying broth? Needham’s Hypothesis: Spontaneous generation-Life forms arose from non-living matter. Spallazani’s Hypothesis:Microbes come from the air. Boiling the broth will kill them. Experimental Designs with flaws John Needham Needham Open flask > Spallazani Closed flask > Lazzaro Spallanzani 1700’s
Louis Pastuer …disproved the idea of spontaneous generation of life. Louis Pasteur ended the debate with his famous swan-neck flask experiment, which allowed air to contact the broth. Microbes present in the dust were not able to navigate the winding bends in the neck of the flask. 1800’s Controlled all of the variables in the experiment--- GOOD EXPERIMENTAL DESIGN
Soooo…what is good science? Objectivityis the key to good science. and following standard procedures.
Designing Experiments Problem: Small Pox an infections disease of humans. • Infected human population dating from 10,000 B.C.E. • The disease killed an estimated 400,000 Europeans annually during the late of the 18th century. • Those infected, 20–60%—and over 80% of infected children—died from the disease. • Smallpox was responsible for an estimated 300–500 million deaths during the 20th century. Solution: ????
The Beginnings of Immunology--using the scientific methodEdward Jenner and the first vaccine: Dr. Jenner was aware of farm workers' belief that if you had cowpox in the past, you wouldn’t get smallpox. COWPOX : Infectious disease that caused mild discomfort, aching, a few pustules, some swelling…symptoms that disappeared in a few days. SMALLPOX: Infectious disease that caused massive disfigurement, sometimes blindness, and often death. FYI- Last known case of Small Pox 1977.
The Beginnings of ImmunologyEdwardJenner and the first vaccine. Question:Does having cowpox make a person immune to smallpox? Hypothesis: If someone is infected with cowpox, then they will be immune to smallpox because having cowpox keeps a person from getting smallpox. Experiment:Jenner made small incisions or punctures in arms of human subjects and rubbed in cowpox material (pus) in order to infect them with cowpox. Analysis & Conclusion: He saw--- that people he had infected with cow pox, when later exposed to smallpox, would get a little bit sick, but never come down with a full-blown case of smallpox. Cowpox infection prevents smallpox infection. Present Results / Peer Evaluation:At first his peers doubted the safety and value of his treatment, but eventually the importance of the cowpox inoculum was recognized. 1800’s – English physician
Vaccination was not without its critics. In this cartoon from 1802, the British satirist James Gillray implied that vaccination caused people to become part cow.
SCIENTIFIC METHOD • A series of steps that scientists use to answer questions and solve problems. • Is not a rigid procedure. • Scientists may use all of the steps or just some of the steps. • They may even repeat some of the steps. • The goal of the scientific method is to come up with reliable answers and solutions to questions.
Scientific Method (Inquiry) Publish Research
Purpose:Observations/ Questions • The scientific method starts with questions about something that is observed. (5 Senses) • How, What, When, Who, Which, Why, or Where? • Initial observations and inferences.
Research • Collect and analyze information to increase your understanding of a topic or issue (question).
Hypothesis • A testable explanation for an answer to an observation, question or problem. If _ [I do this]__ then _[this]__ will happen___because_[why]__.
Experiment/Test • A procedure to test the hypothesis. • An experimenter changes one factor and observes or measures what happens.
Variables (Factors) • The factor that is changed by the experimenter is known as the independent variable. ( IDo.) • The factor that is measured or observed is called the dependent variable. (data) A good or “valid” experiment will only have ONE independent variable!
Constants • The experimenter makes a special effort to control all the factors in an experiment so that they will not effect the outcome. (false results) • These factors are called or constants. • Controls groups are sometimes used to help validate an experiment. All variables the same except for the independent variable (IDV) • Controls are NOT being tested • Controls are also used for COMPARISON
Materials/Procedures • Listed---Specific detail of all of the equipment necessary to complete the experiment. • Numbered steps with specific details.
Results or Data-Analysis Data: Information or observations collected during an experiment. Qualitative=descriptions Quantitative=measurements Analysis- Data is evaluated. Look for trends Look at all data together. Tables and graphs are often used to organize and analyze the data.
Conclusion Discussion and summary of the experiment-based on the analysis of the data. Do the results support the hypothesis? • Discuss possible errors • Investigate again? • Make a new hypothesis
Publish • Results are verified by independent duplication and publication in a peer-reviewed journal • Independent duplication= Two or more scientists from different institutions investigate the same question separately and get similar results. • Peer-reviewed journal. = A journal that publishes articles only after they have been checked for quality byseveral expert, objective scientists from different institutions.
Scientific Theory vs. Law THEORY Explanation for an observation or phenomena that is confirmed by a large amount of evidence or tests (experiments). Example: Germ theory of disease - Infectious diseases result from the action of microorganisms. LAW A statement of a scientific principle that appears to be without exception at the time it is made, and always works the same way under the same conditions; A scientific rule. Example: Newton's First Law of Motion (Law of Inertia) - every object either remains at rest or in continuous motion with constant speed unless acted upon by an outside force. Treponema pallidum - ♪ (Trep-o-neemah pal-lid-um)
So, what's the difference? A SCIENTIFICTHEORY - are typically non-mathematical. A SCIENTIFIC LAW - are often mathematically defined • Looking at things this way helps to explain, in part, why physics and chemistry have lots of "laws" whereas biology has few laws (and more theories). • In biology, it is very difficult to describe all the complexities of life with "simple" (relatively speaking!) mathematical terms.