The Scientific Method: DR HERC The Scientific Method refers to the basic steps scientists use to solve problems… D (D)etermine the Problem R Gather (R)esearch H Form a (H)ypothesis E Carry Out an (E)xperiment Record and Analyze the (R)esults C Draw a (C)onclusion

Step 1: Determine the Problem A good science problem is written as a question, and is one that you can test to find the answer *This is the purpose of your investigation What is the problem or question posed in the “Octopus Pregnancy?” Is it possible for an octopus egg to survive and grow in a human stomach

Step 2: Gather Research Gather data to help you form your hypothesis Research what others have already discovered about your problem (books, magazines, reports, experts, etc.) Observation – using one or more of your senses to collect data Inference – an interpretation of an observation based on evidence or prior knowledge What information did Adam and Jamie gather before beginning their experiment?

Step 3: Form a Hypothesis A hypothesis is a possible explanation of, or answer to your scientific question Worded as an “If…then…because…” statement MUST be testable MUST be based on research Will be supported or disproved by experimentation What was Adam and Jamie’s hypothesis? What did you think would happen?

Step 4: Carry Out Experiment Materials List Detailed list of all supplies needed to carry out your experiment Include amounts needed of each supply Procedures List Step-by-step instructions for how to carry out experiment Must be detailed enough so your experiment could be repeated by someone else

They also include… a CONTROL Controls are things that do not change throughout the experiment These are kept the same throughout each trial What things did Adam and Jamie keep constant throughout their experiment?

What variables did Adam and Jamie include in their experiment? As well as… VARIABLES A variable is a factor that can change in an experiment You may only change one at a time! An independent variable is the one and only variable you’re allowed to change in your experiment this is the variable being tested (x-axis on a graph) A dependent variable is the factor that changes because of your independent variable this is the observed variable (y-axis on a graph) What variables did Adam and Jamie include in their experiment?

Step 4: Carry Out an Experiment Now you may design and carry out an experiment to test your hypothesis Determine controls Consider all possible variables Must include at least two trials ??? How did the Mythbusters team carry out their experiment?

How did Adam and Jamie check and interpret their results? Step 5: Record your Data Recording accurate observations and measurements are necessary to carrying out a valid experiment Once recorded, you can organize your data Perform any necessary calculations Create charts/graphs/data tables to organize data Consider sources of error How did Adam and Jamie check and interpret their results?

Step 6: Draw a Conclusion Interpret your charts, tables, or graphs to help you draw your conclusions Answer your question using data as evidence No octopus here… Based on the data you have gathered, were you able to find the answer to your question? If so, was your hypothesis correct? If no, what other experiment(s) could help you retest your theory? What conclusion can be drawn as a result of this experiment?

Scientific Theory Scientific Theory is an explanation of how or why something happens based on scientific knowledge resulting from repeated observations and experiments A theory is based on thousands of experiments carried out by many different scientists It can be proven to be incorrect as new knowledge is gained from further experiments

Scientific Law A Scientific Law is a statement about how something works that seems to be true all of the time Tells what will happen, but does not necessarily explain why Is less likely to change than a Scientific Theory