BSC 2010 Chapter 1

Defining Biology Science of living organisms Science-From Greek “to know” –Body of knowledge –Method of inquiry

Characteristics of Science Deals with falsifiable concepts Dynamic body of knowledge Open minded approach

Defining Feature of Life Composed of a cell or cells (Cell theory) Sense and respond Reproduce Grow and develop Cycle energy Regulate- homeostasis Display order Contain DNA as hereditary material

Connections- Themes within Biology Evolution –Change in a population over time –Natural selection –Selects for pre- existing traits Unity Diversity

Themes in Biology Emergent Properties –Novel properties –Appear as higher levels of complexity are attained –Due to arrangement and interaction of parts –Not unique to life

Themes in Biology Correlation between structure and function Seen at all levels of organization from atoms to biosphere

Themes in Biology The cell as the basic unit of life both structurally and functionally All cells share common characteristics

Themes in Biology Continuity based on DNA as heritable information All cells contain DNA DNA encodes all proteins found within an organism DNA allows those codes to be passed on to progeny

Themes in Biology Homeostasis Maintenance of conditions within tolerable range Feedback regulation –Negative –Positive

Negative Feedback

Positive Feedback

Reductionism and Systematics Reductionism –Take apart to understand Systematics –Study interactions to understand –Determine evolutionary relationships –Ecosystem dynamics

Levels of Biological Organization Atom Molecule Organelle Cell Tissue Organ Organ system Organism

Levels of Organization Population Community Ecosystem Biosphere ? Universe?

Classification of living Organisms Domain Kingdom Phylum Class Order Family Genus Specie Binomial Nomenclature Systematics leading to entirely different schemes

Bacteria

Archae

Eukarya

Main Types of Scientific Inquiry Hypothesis based Scientific method Observation Question Hypothesis Prediction Experiment Conclusion Discovery based Observations- Use senses to intake data Field studies Information gathering without drawing conclusions Conclusions drawn from observations without experimentation

Types of Reasoning Inductive –Derive generalizations from a number of specific observations –Common in Discovery science Deductive –Draw specific conclusions based on generalizations

Summary Evolution is the over arching concept in biology New properties emerge at each level in the biological hierarchy Organisms interact with their environment exchanging matter and energy Structure and function are correlated at all levels. Cells are the basic functional and structural unit of life Continuity of life is based on heritable information contained within DNA Feedback mechanisms regulate biological systems