Chapter One The Science of Biology Bio A – Mrs. Sleevi

What is science? Facts and ideas Not stagnant new discoveries rejection of some ideas confirmation of other ideas

Why do we study science? Provide explanation of the natural world Understand structure and function of living organisms Understand the interaction between living organisms and the physical world To make predictions ‘Cause it’s neat stuff

Is there such a thing as “settled science”? What does science provide? Proof? Evidence? Conjecture? Certainty? Uncertainty? Science is never 100% settled. Science is about narrowing uncertainty. (scepticalscientist.com)

How do we do science? The Scientific Method Observations/Questions Formulate hypothesis Design controlled experiment Collect/analyze the data Draw conclusions Evaluate the hypothesis based on the outcomes; change as needed; conduct further experiments

What if the hypothesis appears to be wrong?

The controlled experiment Independent variable (IV) deliberately changed in the experiment Values that are “tested” Sometimes referred to as the “I-Change” variable Dependent variable (DV) What is measured Result is expected to vary based upon the value of the IV Constants Those variables that are held the same regardless of the value of the IV

The controlled experiment Redi’s Experiment – YouTube What was the control in Redi’s experiment? How would you describe the control?

Examples of Experimental Design The Effect of the IV on the DV…. The Effect of Different Aged Compost on Bean Plant Growth The Effect of Different Perfumes on Bee Behavior The Effect of Volume of Water on Plant Growth The Effect of Various Concentrations of Chemical X on the Growth of Tomato Plants

Qualitative vs Quantitative Data When conducting experiments…

Do we always collect data from an actual experiment?

Scientific Inquiry Exercise

How is scientific knowledge organized? Scientific Law A concise statement that summarizes the results of a broad spectrum of observations and experiments’ Describes a natural phenonmenon Does not attempt to explain it Often expressed by simple mathematical relationships Gas Laws Thermodynamics Conservation of Energy Conservation of Mass

How is scientific knowledge organized? Theory A thoroughly tested explanation of why experiments give certain results. A theory can never be proved, only disproved Useful to provide mental pictures of objects or processes that cannot be seen Predict the behavior of natural systems under varying circumstances

The anatomy of a scientist…. A scientist is….. Curious Skeptical Creative Open-minded

Are discoveries always what we set out to find? “Chance favors the prepared mind” Louis Pasteur (1822-1895), France “Serendipity” Post-It notes Teflon Penicillin

Preconceived Notions Beware! Bias

How do we share scientific data? √ Peer-reviewed journals Presentations at scientific meetings Blogs Wikipedia √ × ×

Other aspects…. Ethics Morality Although very important to society, pure science is about content. The application of the technology we obtain requires evaluation with respect to its impact and ethics. Biology seeks to understand and define WHAT life is, not WHY life exists. We leave that to the philosophers and theologians and other fellow travelers.

What is Biology? Greek: Bios = Life -ology = study of

Characteristics of Living Things Cells Genetic Code Obtain and use materials for energy (metabolism) Grow/Develop Reproduce (sexual or asexual) Respond to the environment Maintain stable internal environment (homeostasis) Change over time

How is science organized? By discipline Biology Chemistry Physics Geology Others By specialty within the discipline Microbiology Ecology Biochemistry Biopharmaceutical Genetics Zoology Botany

Topics for this semester Technology Chemistry of Life Cells Structure and function Photosynthesis Cellular Respiration Cell Growth Genetics Early Genetics (Mendel) DNA RNA Heredity Genetic Engineering