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ISSUES IN BIOLOGY & THE SCIENTIFIC METHOD. Packet #1 Chapter #1 AP Biology. BIOTERRORISM. BIOTERRORISM. Bioterrorism The use of biochemical agents for terrorist purposes. Biowarfare
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ISSUES IN BIOLOGY & THE SCIENTIFIC METHOD Packet #1 Chapter #1 AP Biology
BIOTERRORISM • Bioterrorism • The use of biochemical agents for terrorist purposes. • Biowarfare • Use of disease-producing microorganisms or biocides to cause death or injury to humans, animals and/or plants • Biochemical Agents • Pathogens • Anthrax • Bacillus anthracis • Smallpox • Variola major • Agriculture pesticides
AVIAN FLU PANDEMIC • Refers to influenza A viruses found chiefly in birds • Some infections, caused by the virus, can be carried over to the human population • Hong Kong 1997 • Virginia 2002 • New York 2003 • Vietnam 2005 • Iraq 2006 • http://www.cdc.gov/flu/avian/gen-info/avian-flu-humans.htm
EMBRYONIC STEM CELLS • Ability to develop in different cell types • Treat diseases, conditions and disabilities • http://stemcells.nih.gov/index.asp
OVER POPULATION • Condition of any organism’s numbers exceeding the carrying capacity of its ecological niche. • How does this relate to humans? • http://www.answers.com/over%20population
EMERGENT DISEASES • http://www.cdc.gov/ncidod/id_links.htm
GLOBAL WARMING • Increase in earth’s average temperature and the climatic impacts that it may have.
BIODIVERSITY • Biodiversity • The variability among living organisms on the earth, including the variability within and between species and within and between ecosystems. • A goal of scientists is to discover the effects of the previously mentioned not only on humans, but the estimated 7 – 20 million species on earth. • How do we do that?
SCIENTIFIC METHOD • Manner for investigating nature • Scientists attempt to construct an accurate, reliable, consistent and non-biased representation of the natural world • Few scientists adhere to the “strict procedures” • Creativity, individuality, distinct
SCIENTIFIC METHOD • Scientific Theories • 2 components • Describes the patterns seen in the natural world • Identifies a process or mechanism responsible for a pattern • Biology • A study of patterns of living things and their processes
SCIENTIFIC METHODCOMMON STEPS • Observation • An observation is made regarding some event or characteristic of the world • A problem is developed • An open-ended question that cannot be answered by a yes or no answer
SCIENTIFIC METHODCOMMON STEPS • Forming a Hypothesis • Postulating a premise • An explanation of the phenomena observed • Predict the existence of other phenomena or predict quantitatively the results of new observations • States results that may be expected from observations and/or from experimental tests • Can be based on one’s experience creativity or a sense of what is practical • Involves critical thinking and critical analysis • Deductive reasoning • Reasoning from a general observation to a specific conclusion • Inductive reasoning • Reasoning from a specific case to the general • Hypothetico Reasoning • Hypothesis developed Prediction deduced Tested against empirically derived data
SCIENTIFIC METHODCOMMON STEPS • Experiment & Experimental Design • Unbiased • Disprove a hypothesis • Evaluate an alternate hypothesis • Null hypothesis • College/University • Testing the hypothesis • Determining whether prediction is correct
SCIENTIFIC METHODCOMMON STEPS • Experiment & Experimental Design • Methods and Procedures • Adaptable • Able to reexamine as new information is collected • Suppose to test a premise • Best when designed to “disprove” a hypothesis • Often said in science that theories can never be proved but only disproved • A hypothesis can never be proven but evidence, collected during experimentation, can be used to support
EXPERIMENT III • Experiment & Experimental Design • Variables must be defined • Dependent Variables • Measureable and observable things • Independent variable • Should be only one during an experiment • Can be manipulated and changed • Controlled variables • Kept constant and not allowed to change • *Control • All experiments should have one • Used as standard f comparison
SCIENTIFIC METHODCOMMON STEPS • Collection of Results & Interpretation of Data • Must use same criteria (technique) for collecting all data • Representation of Data • Tables • Graphs • Interpretation of Data/Statistical Analysis • T-test • Compares the means of two groups • ANOVA • Compares the means of three or more groups • Chi Square • Compares how closely the observed data is to the expected results • *Experimenters should also look at the variance
SCIENTIFIC METHODCOMMON STEPS • Conclusion • Does the experiment match your predictions? • Is your hypothesis supported • Does your results agree with other findings? • Replicate the experiment
Scientific Law • Hypothesis whose predictions have stood up to thorough and rigorous testing with experiments and observations.
LIMITATIONS OF THE SCIENTIFIC METHOD • Some hypotheses are not experimental • Intelligent beings in the universe • Global warming • *Theory of evolution