Scientific Method Chapter 1

What is science? Definition- a body of language based on the study of nature Science is always changing as technology advances Science is based on inquiry that seeks to develop explanations Science is dependent on observation and experimentation Science uses explanations to make useful predictions

How do scientists work? Scientific Method- common steps used by scientists to gather information and solve problems Process used by scientists to solve a problem Steps of scientific method

Observation Act of noting or perceiving objects/ events using senses

Problem Ask a question about what you observe

Hypothesis Definition- testable explanation for a problem based on an educated guess Based on cause and effect relationships (if…..then statement) Example: If soil temperatures rise, then plant growth will increase. Based on preliminary observations and scientific literature (ex. Scientific Journals) Prediction- expected outcome of a test, assuming the hypothesis is correct

Experiment Definition- procedure that tests a hypothesis by collecting information under controlled conditions clear, replicable procedures

Parts of a good/valid experiment -Control group: standard, all conditions kept the same, used for comparison Experimental group- group that you experiment with

Control vs. Experimental Control Group Experimental Group A student wanted to test the effects of sunlight on the growth of plants.

Variables Independent variable (IV)- one thing that’s different Dependent variable (DV)- physically measured Example…Billy Bob wanted to test the effect of different color lights on plant height. Billy Bob planted the same amount of soil in Group A and in Group B. In Group A Billy bob put the plants in normal light and in Group B he tested the effect of blue light.

Collect Data and Analysis Quantitative data- expressed by #’s, obtained by counting or measuring ex. 5 mice, plants grew 20”, 20 cats Qualitative data-descriptive ex. All fish appear healthy, green pea pods

Conclusion State whether your prediction was confirmed or not and try to explain your results. Accept/ reject hypothesis Experimental Error- what errors have caused your hypothesis to be rejected (human error, too many variables, biases) Ways to improve or expand research

Review of Scientific Method 1) Identify a Problem 2) State Observations about the problem 3) Form a Hypothesis about the problem (if…then…) 4) Design an Experiment to test the hypothesis 5) Collect Data 6) Form a Conclusion 7) Retest BrainPop-Scientific Method http://glencoe.mcgraw-hill.com/sites/0078695104/student_view0/brain_pop_movies.html#

Science and Technology Science is both a body of knowledge and a process of finding answers Technology is the practical application of science (ex. Computer, laser) Scientists use and depend on technology, technology improves by increased knowledge from scientists Science and Technology are dependent on each other

Science and Technology Because science and technology are always changing, theories can change Theory- well tested statement that unifies a broad range of observation Theories can change as new evidence becomes available

Limitations of Science Money Availability of equipment Skills