1. Biology Scientific study of life Lays the foundation for asking basic questions about life and the natural world

2. Why Study Biology? To learn how organisms are constructed, how they function, where they live, and what they do To help develop, modify, and refine ideas about life

3. Two Unifying Themes  Hierarchical organization  The power of evolution -

4. Levels of Organization Atom Molecule Cell Tissue Organ Organ System molecule cell tissue organ organ system atom

5. Levels of Organization Multicelled organism Population Community Ecosystem Biosphere multicelled organism community population ecosystem the biosphere

7. Life’s Diversity Millions of living species Millions more now extinct Each species has some unique traits

8. Classifying Life Domain Kingdom Phylum Class Order Family Genus Species

9. Scientific Names Two-part name (binomial) –Humphead parrotfish is Scarus gibbus –First part (Scarus) is genus name –Second name designates a particular species within the genus

10. Classification Systems Organisms are grouped together based on descent from a shared ancestor Three domains exist: Eubacteria (Bacteria) Archaebacteria (Archaea) Eukaryotes (Eukarya)

11. Origin of life Eubacteria Archaebacteria Eukaryotes ProtistansPlantsFungiAnimals Major Groups