1. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 1 Lecture Slides

2. 1.1 The Diversity of Life Biology is the study of living things Living things are diverse There are enough similarities among some living things that they can be grouped into the same kingdom Members of different kingdoms are usually very different from each other

3. Figure 1.1 The six kingdoms of life

4. 1.2 Properties of Life What qualifies something as “living” versus “non- living?” Consider these points  complexity  movement  response to stimulation A life-defining property must be exclusive to living things

5. 1.2 Properties of Life 1. Cellular organization  all living things are comprised of at least one cell 2. Metabolism  all living things process energy which is used to power other processes 3. Homeostasis  all living things maintain relatively stable internal environments to optimize conditions for metabolism and other processes

6. 1.2 Properties of Life 4. Growth and reproduction  all organisms have the capacity for growth and reproduction 5. Heredity  all organisms pass genetic information to future generations from parents to offspring

7. 1.3 The Organization of Life Living things function and interact with each other on many levels The organization of life is a hierarchy of levels of increasing complexity  cellular  organismal  populational

8. Figure 1.4 Levels of organization: cellular level

9. Figure 1.4 Levels of organization: organismal level

10. Figure 1.4 Levels of organization: populational level

11. 1.3 The Organization of Life At higher levels of the living hierarchy, new properties become apparent that were absent at the lower levels These emergent properties result from the interaction of diverse but simpler components Many higher order processes that are hallmarks of life are emergent properties  metabolism  consciousness

12. 1.4 Biological Themes The study of life is organized around general themes 5 biological themes emerge repeatedly at any hierarchical level of biological study

13. 1.4 Biological Themes 1. Evolution  evolution is genetic change in a species over time  the mechanism for evolution is natural selection  the diversity of life is explained by evolutionary processes

14. 1.4 Biological Themes 2. The Flow of Energy  all living things require energy  energy from the sun flows through the living world  organisms acquire energy differently  how much energy is available determines how many and what kinds of organisms can live together in an ecosystem

15. 1.4 Biological Themes 3. Cooperation  as energy and other resources are limiting, many organisms have evolved cooperation as a means of survival  symbiosis describes when two species live in direct contact

16. 1.4 Biological Themes 4. Structure Determines Function  evolution favors structures that function in an adaptive manner  many structures are specialized for a particular function  the convergence of structure and function occurs at levels of the organizational hierarchy

17. 1.4 Biological Themes 5. Homeostasis  homeostasis is a physiological condition of “steady- state”  the internal environment of organisms is relatively stable  organisms act to control their internal environments so that the complex processes of metabolism function efficiently

18. 1.5 Stages of a Scientific Investigation Biology is a dynamic science with new ideas appearing and replacing old ones Scientists systematically conduct experiments to evaluate hypotheses about observed phenomena

19. 1.5 Stages of a Scientific Investigation The scientific process can be said to have six stages 1. Observation  science begins with careful observation of natural phenomena 2. Hypothesis  scientists make an educated guess that might be true  often scientists formulate multiple ideas about a phenomenon; these are called alternative hypotheses

20. 1.5 Stages of a Scientific Investigation 3. Predictions  if a hypothesis is correct, then specific consequences can be expected 4. Testing  scientists conduct experiments to attempt to verify predictions made by hypotheses

21. 5. Controls  experiments usually employ a parallel design scientists use a control to assess the influence of potential factors, called variables conditions stay the same in the control in comparison to the variable condition 6. Conclusion  a hypothesis that has been tested and not rejected is tentatively accepted 1.5 Stages of a Scientific Investigation

22. Fig.1.5 The scientific process

23. 1.6 Theory and Certainty The term “theory” means different things to different audiences  to scientists, a theory represents certainty and is a unifying explanation for a broad range of observations  to the general public, a theory implies a lack of knowledge or guess

24. 1.6 Theory and Certainty Scientists’ acceptance of theory is provisional  the possibility always remains that future evidence will cause a theory to be revised The process of science is not just trial- and-error but involves judgment and intuition

25. 1.6 Theory and Certainty science has limitations  it is limited to organisms and processes that can be observed and measured supernatural and religious phenomena are beyond the scope of science  there are also practical limits science cannot be relied upon to solve all problems

26. 1.7 Four Theories Unify Biology as a Science 1. The Cell Theory 2. The Gene Theory 3. The Theory of Heredity 4. The Theory of Evolution

27. The Cell Theory all organisms are composed of at least one cell the cell is the most basic unit of life all cells come from pre-existing cells

28. The Gene Theory genetic information is encoded in molecules of deoxyribonucleic acid (DNA) genes encode specific proteins or RNA or act to regulate other genes the proteins and RNA encoded by an organism’s genes determine what it will be like in terms of form and function

29. Figure 1.10 The gene theory

30. The Theory of Heredity genes are passed down generations as discrete units  Mendel’s theory of heredity gave rise to the field of genetics  chromosomal theory of inheritance located Mendelian genes on chromosomes

31. The Theory of Evolution All living organisms are related to one another in a common tree of descent  the six kingdoms of life can be grouped into three domains Charles Darwin’s theory of evolution explains the unity and diversity of life as “descent with modification”  scientists have been able to identify changes in individual genes that are responsible for differences among individuals

32. Fig. 1.12 The three domains of life

33. Figure 1.13 The theory of evolution

34. Inquiry & Analysis What is the dependent variable? Is the size of the ozone hole increasing? Why are the rates of increase different between 1980 - 1990 and 1995 - 2005? Is the Size of the Ozone Hole Increasing?