Chapter 1: What is Life? • Hierarchy, levels of biological structure Fig 1.3 Fig 1.10, 1.11 Fig 1.16, 1.17 Chapter 1: What is Life? • Hierarchy, levels of biological structure • Properties of life (at least 7) • Evolution, Unity and Diversity • Scientific Method

Life’s Hierarchical Order (figs 1.2, 2.1) (atoms), (organelles) Cells Tissues Organs Organism Population * Community * Ecosystem * Emergent properties

Emergent Properties: Novel properties which result from interactions between components. An organism is a living whole, greater than the sum of its parts.

Is it alive? (fig 1.3) Organisms are open systems & interact with their environment Fig 1.3 lists 7 common characteristics Why aren’t bubbles alive? Demo… Why aren’t viruses alive?

What is life? NASA’s Working Definition of Life Life is capable of metabolism, (chemical reactions which utilize energy and also synthesize its cellular constituents.) Second, life is capable of self replication. Third, life can evolve in order to adapt to environmental changes. Life is a community of organisms which must interact with their nonliving environment through processes called biogeochemical cycles.

Examples of Cells

Homeostasis Fig 1.8 Feedback mechanisms of living things Negative Ex. Blood glucose levels Body temp. Positive Ex. Breast feeding Blood clotting

Domain (3) Classifying Life Fig 1.10 K,P,C,O,F,G,S General to specific 5? Classifying Life Fig 1.10 K,P,C,O,F,G,S General to specific

Fig. 1.11 review page 11 Domains of Life (3) 1. Bacteria (prokaryotes, most ancient) 2. Archaea (prokaryotes, extreme ) 3. Eukarya (eukaryotes = protists, plants, animals, fungi)

Hypothetico-deductive Reasoning

Sources Campbell, Reece, Mitchell. Biology, 5th Ed. 1999, Chapter one. Pgs. 1-21. Campbell, Reece, Mitchell. Biology, 5th Ed. 1999, Presentations CD-ROM. Click art CD-ROM, Broderbund.

Unit One, the Chemistry of Life T.O.D. Dr’s. Mario Molina, Paul Crutzen, F. Sherwood Rowland. 1995 Nobel Prize Ozone Layer and pollutants

IS IT ALIVE?