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Biology: What is it good for?. Why study biology ?. “ Gossip Can Have Social and Psychological Benefits ” Science Daily, January 17, 2012 “ Why Coffee Drinking Reduces the Risk of Type 2 Diabetes ” , ACS ' Journal of Agricultural & Food Chemistry, ScienceDaily , January 11, 2012
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Why study biology? • “Gossip Can Have Social and Psychological Benefits” Science Daily, January 17, 2012 • “Why Coffee Drinking Reduces the Risk of Type 2 Diabetes”, ACS' Journal of Agricultural & Food Chemistry, ScienceDaily, January 11, 2012 • “Kids who get recommended sleep least likely to be obese” University of Chicago and University of Louisville, Pediatrics, January 24, 2011 • “Promising Results in Mice On Needle-Free Candidate Universal Vaccine Against Various Flu Viruses” ScienceDaily, December 8, 2011
So then, what is biology? • What is science? • A process used to solve problems and understand natural events • Involves the scientific method • Biology: the science that deals with life. • Bio - life; ology - study of • Subcategories • Ecology Microbiology Botany • Zoology Cytology Parasitology • Mammology Genetics Anatomy
What makes something alive? Hydrogen Oxygen Carbon Nitrogen Phosphorous Sulfur Hydrogen Oxygen Carbon Nitrogen Phosphorous Sulfur
Significance of biology • Biology has significantly contributed to our high standard of living (for better or worse).
Advances in food production BMR silage corn - Brown midrib (BMR) gene mutation creates corn with less lignin - Less lignin= more digestible corn - More dry matter intake = more milk! BMR corn
Advances in disease control (vaccines) Vaccine preventable diseases: Smallpox Polio Chickenpox Whooping cough (pertussis) Measles Hepatitis Influenza Tetanus Diptheria HPV Etc…. And what’s next… HIV? Cancer?
Advances in gene therapy Gene therapy successes Severe combined immunodeficieny disorder (SCID) Chronic myelogenous leukemia Parkinson’s disease And more… Cartoon by: Dr. Donald J DavidsonDalin@devondavidson.eclipse.co.ukhttp://www.devondavidson.eclipse.co.uk/Art_Gallery.html
What led to these advances? Use of the scientific method • A way of gaining information about the world that involves • forming possible solutions to questions • rigorous testing to determine if the solutions are supported • continual checking and rechecking to make sure that previous conclusions are still supported • modification of unsupported conclusions
Scientists look for cause and effect relationships • Causative: Events have a cause and effect relationship • When one event happens as a direct result of a preceding event. • Example: Lightning causes thunder • Correlative: Events that happen simultaneously are correlated, but • may or may not have a cause and effect relationship • Example: Autumn and falling leaves • Not the season but the light period and temperature
2 components of the scientific method Hypothesis-based science (Deductive reasoning) Observation Questioning and exploration Forming a hypothesis Testing hypothesis with controlled experiment Collecting/analyzing data Deductive reasoning to reach conclusion Discovery science (Inductive reasoning) Observation Recording data Analysis of data Inductive reasoning to reach conclusion
How do you do hypothesis-based science? 1. Ask a question 2. Propose an answer or hypothesis (hypothesis- singular; hypotheses- plural) 3. Hypotheses must… • Be testable • Make the least possible assumptions • Create an “If ………… then …………….”
How do you do hypothesis-based science? 4. Create an experiment • An experiment is a re-creation of an occurrence. • It tests whether or not the hypothesis can be supported or rejected. 5. Experiments must be controlled • This means that all aspects except for one variable must be kept constant • Experiments contain two groups: • Experimental group: variable is altered • Control group: variable is not altered
Experimental design- what is important? • Independent variable: The variable that is altered • Experiments should have only ONE independent variable (what you change to see if it has an affect on the outcome) • Dependant variable/s: The variables that change in response to the independent variable • Changes in the dependent variables are documented as data (what are the responses to the independent variable)
What do we do with all these dependent variables (data)?Form Conclusions
What do we do with all these dependent variables (data)?Form Conclusions What do we do with all these conclusions?
What do we do with all these dependent variables (data)?Form Conclusions What do we do with all these conclusions?Form Theories
Theory vs Law • Theory: a widely accepted, plausible general statement about a fundamental concept in science that is well supported by many experiments and/or conclusions • EXAMPLE: The cell theory states that “all life is composed of cells” • Scientific Law: a uniform and constant fact of nature that describes what happens in nature. • EXAMPLE: Gravity
Yes, there are limits to science • The scientific method can only be applied to questions that have a factual base. • Questions of morality, values, social issues and beliefs cannot be tested scientifically. • Science is limited by people. • The sun orbits the earth. • But, science is self-correcting. • New data shapes new hypotheses. • The earth rotates on its axis, so maybe the earth orbits the sun.
You can only disprove something with the scientific method… You can not prove it!
Independent study… Design an experiment
Flu pandemics Future predictions U.S…. Infection would peak at 60 days 33% population sick (50% mortality) Worldwide… 1 billion sick/ 7 million die www.cdc.gov
Question:What affect will the recent swine fluepidemic have on flu vaccination rates?
Lets form a hypothesis and conductan experiment… • Hypothesis: • Independent variable: • Dependent variable: • Data: • Conclusion: • Any problems with this experimental design??