chapter 1: what is life?

Chapter 1: What is Life?

• Hierarchy, levels of biological structure

• Properties of life (at least 7)

• Evolution, Unity and Diversity

• Scientific Method

Fig 1.3

Fig 1.10, 1.11

Fig 1.16, 1.17

Fig 1.3

Fig 1.10, 1.11

Fig 1.16, 1.17

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?

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.

What is life?NASA’s Working Definition of Life

Examples of Cells

Feedback mechanisms of living things

Negative Ex. Blood glucose

levels Body temp.

Positive Ex. Breast feeding Blood clotting

HomeostasisFig 1.8

Classifying Life

Fig 1.10

K,P,C,O,F,G,S

General to specific

Domain (3)5?

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?