Scientific Method State a Problem Form a Hypothesis. Scientific Method = step-by-step method of problem solving used by scientists step-by-step method or plan of gathering, organizing, & communicating information You will use the Scientific Method to complete labs and inquiries. State a Problem Form a Hypothesis. 3) Experiment / Test the Hypothesis 4) Analyze Data 5) Conclusion – Accept or Reject the hypothesis P-H-E-A-C

Identify a Problem Hypothesis Problems are found by: Making observations (with your five senses) OR Research Hypothesis Hypothesis = possible explanation for a question or problem Must be able to be tested. Often written as IF…THEN… statements IF the plants does not receive water, THEN it will wilt.

Experiment Experiment = test of the hypothesis Controlled experiment = test only 1 variable. Independent/ManipulatedVariable – one that is CHANGED DIRECTLY by the experimenter Dependent/Responding Variable – one that RESULTS DUE TO THE CHANGE When graphing variables: the independent goes on the X-axis the dependent goes on the Y-axis Dependent Independent

Experiment Control = used for comparison NO experiment is done on the control (Used to see if the expected happens even without the experiment) Constant(s) – everything else in the experiment should be held constant or the same EXCEPT that one variable which is being tested.

Observation: A scientists observes a dog salivating Hypothesis: If there is food , then the dog will salivate. Independent Variable : Dog’s exposure to food (maybe tested at various distance from the dog) Dependent Variable: The amount of salivation by the dog Control: A dog with no food exposure Constants: same amount & type of food, same environment, etc.

NEVER CHANGE YOUR RESULTS TO FIT THE HYPOTHESIS! Analyze Data Data = information Two types of data from an experiment: 1) Qualitative – uses descriptive words Ex. greener, faster 2) Quantitative –uses numbers Ex. 5 meters, 25 days *this type is often graphed to look for trends Conclusion 1) ACCEPT the hypothesis & REPEAT the experiment FOR VALIDITY (to make sure the results are correct) OR 2) REJECT the hypothesis & FORM a NEW HYPOTHESIS NEVER CHANGE YOUR RESULTS TO FIT THE HYPOTHESIS!

What are scientific models & how are they useful? Model - map, diagram, illustration, etc. - makes it easier to understand things that might be too difficult to observe directly 2 types: Physical --such as a globe Mental – diagram of an atom, electron configuration

TOOLS OF SCIENTISTS What happens next? A well tested hypothesis can become a theory A Theory ALWAYS observed to be true can become a LAW Hypothesis Theory Law (least certainty) (most certainty) TOOLS OF SCIENTISTS Scientific Method - PHEAC Metric System –use this measurement system because its international, easier communication Microscopes Cell Culturing (growing many cells from a few) Cell Fractionalization (breaks cells & separates out the cell parts)

Why use science? Technology - the application of science for mankind’s benefit Ex. Medicines, electronics, vehicles Applying science sometimes raises ETHICAL questions Ethics -debate over right or wrong Ex. Cloning, picking the sex of a child, etc.

Metric System/ SI Meter Gram Liter Second Celsius Temperature Volume Mass Length Time

Measuring Tools Temperature thermometer Volume beaker, graduated cylinder Mass triple beam balance Length meter stick, ruler Time watch, clock