Chapter 1: The Scientific Method Leaving Certificate Biology Higher Level

The Study of Biology Biology is the study of living things –Ecology –Physiology –Anatomy

The Scientific Method 1.Observation: taking in of information received about the natural world 2.Hypothesis: an educated guess/idea based on an observation 3.Experimentation: an experiment is a test designed to prove/disprove a hypothesis 4.Collection of data: data are results obtained after carrying out an experiment 5.Conclusions: explaining the results 6.Analysis: explaining new knowledge in relation to existing knowledge 7.Reporting and publishing results: describing and releasing results to other scientists and the public 8.Development of theory and principle: a theory is a comprehensive explanation; a law is a definite, factual explanation of an important aspect of nature

Principles of Experimentation Careful planning and design Safety (e.g. wearing gloves and lab coat) Experimental control: a control is a factor in an experiment that provides a standard upon which results may be compared Sample size: (larger sample size gives a better representation in the results) Random selection: (e.g. clinical trials must include younger people as well as older) Replicates: a replicate is a repeat of an experiment) Double-blind testing: (doctor does not know who has been given an active drug)

Limitations of the Scientific Method 1.Extent of our basic knowledge: lack of knowledge leads to inadequate hypotheses 2.Basis of investigation: lack of technology/materials/equipment 3.Interpretation of results: scientists may interpret results differently 4.Application to a changing natural world: information obtained from organisms in the past may not be valid today – they may have to be repeated 5.Accidental discovery: experiments may have gone completely “wrong” – i.e. “we did not get the desired result” or “we made an error in preparation and an unexpected result is obtained”; e.g. discovery of penicillin