Science Skills Biology 11

Scientific Method A problem solving approach in science Uses a series of logical steps The traditional basis for the acceptance of new knowledge The main approach to designing an experiment Observation Hypothesis Experiments Support Hypothesis CONCLUSION REPORT Reject Hypothesis New Questions

Experimental Design Experiments Are used to investigate a hypothesis. Give strength to a hypothesis but cannot prove it. One hypothesis may generate any number of experiments. Usually, an experiment in biology involves 2 groups: a control group A variable group, in which everything is kept the same as the control group, except the one factor the experimenter wishes to investigate

e.g. pond water pond water + waste (control) (variable) Questions: Does waste water have an effect on life in pond water? All other external factors are kept the same If there are changes, one can conclude that waste appears to have some effect on life in pond water Further Questions: What kind of waste water? Different types of pond water?

Hypothesis vs. Theory Hypothesis an “educated guess”, explanation of phenomenon usually based on some initial observations or understanding leads to experimentation cannot be proved only supported or rejected Theory takes into account the results of many hypotheses (explains many observations) has been tested and retested many times can be used to make successful predictions

Read pg. 4-15