1. BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Neil A. Campbell Jane B. Reece Lawrence G. Mitchell Martha R. Taylor From PowerPoint ® Lectures for Biology: Concepts & Connections CHAPTER 1 Introduction: The Scientific Study of Life Modules 1.1 – 1.3

2. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The lives of gray-headed flying foxes are closely entwined with the lives of the eucalyptus trees that form their habitat –Eucalyptus trees provide food and roosting sites for the flying foxes –Flying foxes aid in eucalyptus pollination and help disperse the resulting seeds Life in the Trees

3. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Flying foxes are becoming an endangered species, partly because of habitat destruction

4. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Biology is the scientific study of life Interactions between different kinds of organisms affect the lives of all –Recall the example of flying foxes and eucalyptus trees THE SCOPE OF BIOLOGY

5. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A structural hierarchy of life, from molecules to ecosystems, defines the scope of biology An ecosystem consists of: –all organisms living in a particular area –all nonliving physical components of the environment that affect the organisms (soil, water) 1.1 Life’s levels of organization define the scope of biology

6. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings At the top of life’s hierarchy is the ecosystem Ecosystems include: –all the organisms in an area, which make up a community –interbreeding organisms of the same species, a population ECOSYSTEM LEVEL Eucalyptus forest COMMUNITY LEVEL All organisms in eucalyptus forest POPULATION LEVEL Group of flying foxes ORGANISM LEVEL Flying fox ORGAN SYSTEM LEVEL Nervous system ORGAN LEVEL Brain Brain Spinal cord Nerve TISSUE LEVEL Nervous tissue CELLULAR LEVEL Nerve cell MOLECULAR LEVEL Molecule of DNA Figure 1.1

7. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Organisms are made up of: –organ systems –organs –tissues –cells –molecules ECOSYSTEM LEVEL Eucalyptus forest COMMUNITY LEVEL All organisms in eucalyptus forest POPULATION LEVEL Group of flying foxes ORGANISM LEVEL Flying fox ORGAN SYSTEM LEVEL Nervous system ORGAN LEVEL Brain Brain Spinal cord Nerve TISSUE LEVEL Nervous tissue CELLULAR LEVEL Nerve cell MOLECULAR LEVEL Molecule of DNA Figure 1.1

8. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings In discovery science, scientists describe some aspect of the world and use inductive reasoning to draw general conclusions –Example: scientists have described how newborn flying foxes cling to their mother’s chest for the first weeks of life 1.2 Scientists use two main approaches to learn about nature THE PROCESS OF SCIENCE Figure 1.2

9. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Inductive vs. Deductive Reasoning INDUCTIVE REASONING Discovery science can lead to important conclusions based on inductive reasoning. We derive generalizations based on a large number of specific observations. Example: The sun always rises in the east. All organisms are made of cells. DEDUCTIVE REASONING Logic flows in the opposite direction, from general to specific. Example:If all organisms are made of cells (premise 1), and humans are organisms (premise 2), then humans are composed of cells (deductive prediction about a specific case).

10. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings In hypothesis-driven science, scientists use the “scientific method” –They propose a hypothesis –They make deductions leading to predictions –They then test the hypothesis by seeing if the predictions come true

11. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The main steps of the scientific method 1.3 With the scientific method, we pose and test hypotheses Observation Question Hypothesis Prediction Test: Experiment or additional observation Test does not support hypothesis; revise hypothesis or pose new one Test supports hypothesis; make additional predictions and test them Figure 1.3A

12. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Deductive reasoning is used in testing hypotheses –If a hypothesis is correct, and we test it, then we can expect a particular outcome Case study: flashlight failure Figure 1.3B

13. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Experiments designed to test hypotheses must be controlled experiments Control groups must be tested along with experimental groups for the meaning of the results to be clear

14. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Case study: spider mimicry Pounce rate (% of trials in which spider jumped on fly) Control group (untreated flies) Experimental group (wing markings masked) Figure 1.3C Figure 1.3D

15. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Examples of hypotheses: 1. The markings and wing-waving of spider mimic flies increases their survival by causing jumping spiders to flee. 2. If the flies’ wing markings are masked with a dye, then jumping spiders should pounce on the marked flies more often.

16. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Another test of the spider mimic hypothesis: wing transplants Number of stalk and attack responses by spiders Wing markings Normal spider mimic Figure 1.3E Wing waving Mimic with mimic wing transplant ControlsExperimentals Mimic with housefly wing transplant Housefly with mimic wing transplant Normal housefly

17. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Grouping organisms by fundamental features helps make the vast diversity of life manageable for study Scientists classify organisms into a hierarchy of broader and broader groups 1.4 The diversity of life can be arranged into three domains EVOLUTION, UNITY, AND DIVERSITY

18. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Prokaryotic vs. Eukaryotic Cells

19. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Tree of Life

20. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Most classification schemes group organisms into three domains: –Domain Bacteria Figure 1.4A, B –Domain Archaea

21. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings –Domain Eukarya Figure 1.4C-F

22. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Six Kingdoms of Life Archaebacteria (Ch 27) Eubacteria (Ch 27) Protista (Ch 28) Fungi (CH 31) Plantae (Ch 29-30) Animalia (Ch 32-34)

23. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings All organisms share a set of common features, signs of unity in life’s vast diversity –All are made of cells –All have DNA as their genetic blueprint These orchids show the variety possible within one species 1.5 Unity in diversity: All forms of life have common features Figure 1.5A

24. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings DNA is made of chemical units called nucleotides Each species has its own nucleotide sequence Figure 1.5B

25. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The genetic information in DNA underlies all of the features that distinguish life from nonlife –Order and regulation –Growth and development –Use of energy from the environment –Response to environmental stimuli –Ability to reproduce –Evolutionary change

26. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Charles Darwin is a central figure in biology He synthesized the theory of evolution by natural selection –A theory in science is a comprehensive idea with broad explanatory power Evolution is the core theme of biology 1.6 Evolution explains the unity and diversity of life Figure 1.6A

27. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The theory of natural selection explains the main mechanism whereby all species of organisms change, or evolve Figure 1.6B (1) Population with varied inherited traits (2) Elimination of individuals with certain traits (3) Reproduction of survivors

28. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Evolution happens when populations of organisms with inherited variations are exposed to environmental factors that favor the success of some individuals over others –Natural selection is the editing mechanism –Evolution is based on adaptations Figure 1.6C

29. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The theory of natural selection applies to all levels in life’s hierarchy In an ecosystem, these interactions make up a complex web of relationships –The functional aspects of an ecosystem come from the structure of the ecosystem’s web 1.7 Living organisms and their environments form interconnecting webs

30. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A web of interactions in a rain forest ecosystem Figure 1.7A

31. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Plants, or plant products, are the ultimate sources of food in an ecosystem –This African sunbird is consuming nectar, a plant product Figure 1.7B

32. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Chemical nutrients cycle within an ecosystem’s web –Energy flows in and out constantly Figure 1.7C Sun Inflow of light energy AirChemical energy Cycling of chemical nutrients Organisms Soil ECOSYSTEM Loss of heat energy

33. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Biology is connected to a great number of important issues –Environmental problems and solutions –Genetic engineering –Medicine 1.8 Connection: Biology is connected to our lives in many ways BIOLOGY AND EVERYDAY LIFE Figure 1.8A

34. Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Many technological advances stem from the scientific study of life Evaluating everyday reports in the press about a large range of subjects requires critical thinking and some familiarity with many areas of biology –In order to understand how rain forest destruction impacts global climate, it is important to understand biology from the molecular to the ecosystem level Figure 1.8B