Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
PowerPoint Lectures for
Biology, Seventh Edition
...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Overview: Biology’s Most Exciting Era
• Biology...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The phenomenon we call life
– Defies a simple, ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• We recognize life
– By what living things do
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Some properties of life
Figure 1.2
(c) Response...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.1: Biologists explore life from the
m...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
A Hierarchy of Biological Organization
• The hier...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• From the biosphere to organisms
Figure 1.3
1 Th...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• From cells to molecules
Cell
8 Cells
6 Organs a...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
A Closer Look at Ecosystems
• Each organism
– Int...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Ecosystem Dynamics
• The dynamics of any ecosyste...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Energy Conversion
• Activities of life
– Require ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The exchange of energy between an organism
and ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Energy flows through an ecosystem
– Usually ent...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
A Closer Look at Cells
• The cell
– Is the lowest...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Cell’s Heritable Information
• Cells contain ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The molecular structure of DNA
– Accounts for i...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Two Main Forms of Cells
• All cells share certain...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Eukaryotic cells
– Are subdivided by internal m...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Prokaryotic cells
– Lack the kinds of membrane-...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.2: Biological systems are much
more t...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Emergent Properties of Systems
• Due to incre...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Power and Limitations of Reductionism
• Reduc...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The study of DNA structure, an example of
reduc...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Systems Biology
• Systems biology
– Seeks to crea...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
CELL
Nucleu
s
Cytoplasm
Outer membrane
and cell s...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Systems biology
– Is now taking hold in the stu...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Feedback Regulation in Biological Systems
• A kin...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• In feedback regulation
– The output, or product...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• In negative feedback
– An accumulation of an en...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• In positive feedback
– The end product speeds u...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.3: Biologists explore life across its...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Grouping Species: The Basic Idea
• Taxonomy
– Is ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Classifying life
Species Genus Family Order Cla...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Three Domains of Life
• At the highest level,...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Domain Bacteria and domain Archaea
– Consist of...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Life’s three domains
Figure 1.15
100 µm
0.5 µm
...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Unity in the Diversity of Life
• As diverse as li...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.4: Evolution accounts for life’s unit...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The evolutionary view of life
– Came into sharp...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The Origin of Species articulated two main
poin...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Natural Selection
• Darwin proposed natural selec...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Natural selection is the evolutionary process t...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• The products of natural selection
– Are often e...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Tree of Life
• Many related organisms
– Have ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Darwin proposed that natural selection
– Could ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Each species is on twig of a branching tree of
...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.5: Biologists use various forms of
in...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Discovery Science
• Discovery science
– Describes...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Types of Data
• Data
– Are recorded observations
...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Induction in Discovery Science
• In inductive rea...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Hypothesis-Based Science
• In science, inquiry th...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Role of Hypotheses in Inquiry
• In science, a...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• We all use hypotheses in solving everyday
probl...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Deduction: The “If…then” Logic of Hypothesis-Base...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
A Closer Look at Hypotheses in Scientific Inquiry...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Myth of the Scientific Method
• The scientifi...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• In mimicry
– A harmless species resembles a har...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• In this case study
– Mimicry in king snakes is ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Field Experiments with Artificial Snakes
• To tes...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• After a given period of time
– The researchers ...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Designing Controlled Experiments
• Experiments mu...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Limitations of Science
• Science cannot address s...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Theories in Science
• A scientific theory
– Is br...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Model Building in Science
• Models of ideas, stru...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
The Culture of Science
• Science is a social acti...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
Science, Technology, and Society
• Technology
– A...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Concept 1.6: A set of themes connects the
conce...
Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings
• Eleven themes that unify biology
Table 1.1
Upcoming SlideShare
Loading in …5
×

Chapter 1 exploring life.Campbell

549 views

Published on

Published in: Science, Technology, Education
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total views
549
On SlideShare
0
From Embeds
0
Number of Embeds
2
Actions
Shares
0
Downloads
11
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Chapter 1 exploring life.Campbell

  1. 1. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings PowerPoint Lectures for Biology, Seventh Edition Neil Campbell and Jane Reece Lectures by Chris Romero Chapter 1 Exploring Life
  2. 2. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Overview: Biology’s Most Exciting Era • Biology – Is the scientific study of life
  3. 3. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The phenomenon we call life – Defies a simple, one-sentence definition Figure 1.1
  4. 4. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • We recognize life – By what living things do
  5. 5. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Some properties of life Figure 1.2 (c) Response to the environment (a) Order (d) Regulation (g) Reproduction(f) Growth and development (b) Evolutionary adaptation (e) Energy processing
  6. 6. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.1: Biologists explore life from the microscopic to the global scale • The study of life – Extends from the microscope scale of molecules and cells to the global scale of the entire living planet
  7. 7. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings A Hierarchy of Biological Organization • The hierarchy of life – Extends through many levels of biological organization
  8. 8. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • From the biosphere to organisms Figure 1.3 1 The biosphere
  9. 9. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • From cells to molecules Cell 8 Cells 6 Organs and organ systems 7 Tissues 10 Molecules 9 Organelles 50 µm 10 µm 1 µm Atoms Figure 1.3
  10. 10. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings A Closer Look at Ecosystems • Each organism – Interacts with its environment • Both organism and environment – Are affected by the interactions between them
  11. 11. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Ecosystem Dynamics • The dynamics of any ecosystem include two major processes – Cycling of nutrients, in which materials acquired by plants eventually return to the soil – The flow of energy from sunlight to producers to consumers
  12. 12. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Energy Conversion • Activities of life – Require organisms to perform work, which depends on an energy source
  13. 13. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The exchange of energy between an organism and its surroundings – Often involves the transformation of one form of energy to another
  14. 14. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Energy flows through an ecosystem – Usually entering as sunlight and exiting as heat Producers (plants and other photosynthetic organisms) Consumers (including animals) Sunlight Chemical energy Heat Heat Ecosystem Figure 1.4
  15. 15. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings A Closer Look at Cells • The cell – Is the lowest level of organization that can perform all activities required for life 25 µmFigure 1.5
  16. 16. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Cell’s Heritable Information • Cells contain chromosomes made partly of DNA, the substance of genes – Which program the cells’ production of proteins and transmit information from parents to offspring Egg cell Sperm cell Nuclei containing DNA Fertilized egg with DNA from both parents Embyro’s cells with copies of inherited DNA Offspring with traits inherited from both parentsFigure 1.6
  17. 17. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The molecular structure of DNA – Accounts for it information-rich nature DNA Cell Nucleotide A C T A T A C C G G T A T A (b) Single strand of DNA. These geometric shapes and letters are simple symbols for the nucleotides in a small section of one chain of a DNA molecule. Genetic information is encoded in specific sequences of the four types of nucleotides (their names are abbreviated here as A, T, C, and G). (a) DNA double helix. This model shows each atom in a segment of DNA.Made up of two long chains of building blocks called nucleotides, a DNA molecule takes the three-dimensional form of a double helix. Figure 1.7 Nucleus
  18. 18. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Two Main Forms of Cells • All cells share certain characteristics – They are all enclosed by a membrane – They all use DNA as genetic information • There are two main forms of cells – Eukaryotic – Prokaryotic
  19. 19. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Eukaryotic cells – Are subdivided by internal membranes into various membrane-enclosed organelles
  20. 20. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Prokaryotic cells – Lack the kinds of membrane-enclosed organelles found in eukaryotic cells EUKARYOTIC CELL Membrane Cytoplasm Organelles Nucleus (contains DNA) 1 µm PROKARYOTIC CELL DNA (no nucleus) Membrane Figure 1.8
  21. 21. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.2: Biological systems are much more than the sum of their parts • A system – Is a combination of components that form a more complex organization
  22. 22. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Emergent Properties of Systems • Due to increasing complexity – New properties emerge with each step upward in the hierarchy of biological order
  23. 23. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Power and Limitations of Reductionism • Reductionism – Involves reducing complex systems to simpler components that are more manageable to study
  24. 24. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The study of DNA structure, an example of reductionism – Has led to further study of heredity, such as the Human Genome Project Figure 1.9
  25. 25. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Systems Biology • Systems biology – Seeks to create models of the dynamic behavior of whole biological systems • With such models – Scientists will be able to predict how a change in one part of a system will affect the rest of the system
  26. 26. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings CELL Nucleu s Cytoplasm Outer membrane and cell surface Figure 1.10
  27. 27. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Systems biology – Is now taking hold in the study of life at the cellular and molecular levels – Includes three key research developments: high-throughput technology, bioinformatics, and interdisciplinary research teams
  28. 28. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Feedback Regulation in Biological Systems • A kind of supply-and-demand economy – Applies to some of the dynamics of biological systems
  29. 29. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • In feedback regulation – The output, or product, of a process regulates that very process
  30. 30. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • In negative feedback – An accumulation of an end product slows the process that produces that product B A C D Enzyme 1Enzyme 1 Enzyme 2 Enzyme 3 D D D D D D D D DD C B A Negative feedback Figure 1.11
  31. 31. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • In positive feedback – The end product speeds up production WW X Y Z Z Z Z Z Z Z Z Z Z Z Z Z Z ZZ Z Z Z Y X Enzyme 4 Enzyme 5 Enzyme 6 Enzyme 4 Enzyme 5 Enzyme 6 Positive feedback Figure 1.12
  32. 32. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.3: Biologists explore life across its great diversity of species • Diversity is a hallmark of life Figure 1.13
  33. 33. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Grouping Species: The Basic Idea • Taxonomy – Is the branch of biology that names and classifies species according to a system of broader and broader groups
  34. 34. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Classifying life Species Genus Family Order Class Phylum Kingdom Domain Mammalia Ursus ameri- canus (American black bear) Ursus Ursidae Carnivora Chordata Animalia Eukarya Figure 1.14
  35. 35. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Three Domains of Life • At the highest level, life is classified into three domains – Bacteria – Archaea – Eukarya
  36. 36. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Domain Bacteria and domain Archaea – Consist of prokaryotes • Domain Eukarya, the eukaryotes – Includes the various protist kingdoms and the kingdoms Plantae, Fungi, and Animalia
  37. 37. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Life’s three domains Figure 1.15 100 µm 0.5 µm 4 µmBacteria are the most diverse and widespread prokaryotes and are now divided among multiple kingdoms. Each of the rod-shaped structures in this photo is a bacterial cell. Protists (multiple kingdoms) are unicellular eukaryotes and their relatively simple multicellular relatives.Pictured here is an assortment of protists inhabiting pond water. Scientists are currently debating how to split the protists into several kingdoms that better represent evolution and diversity. Kingdom Plantae consists of multicellula eukaryotes that carry out photosynthesis, the conversion of light energy to food. Many of the prokaryotes known as archaea live in Earth‘s extreme environments, such as salty lakes and boiling hot springs. Domain Archaea includes multiple kingdoms. The photo shows a colony composed of many cells. Kindom Fungi is defined in part by the nutritional mode of its members, such as this mushroom, which absorb nutrientsafter decomposing organic material. Kindom Animalia consists of multicellular eukaryotes that ingest other organisms. DOMAIN ARCHAEA
  38. 38. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Unity in the Diversity of Life • As diverse as life is – There is also evidence of remarkable unity Cilia of Paramecium. The cilia of Paramecium propel the cell through pond water. Cross section of cilium, as viewed with an electron microscope 15 µm 1.0 µm 5 µm Cilia of windpipe cells. The cells that line the human windpipe are equipped with cilia that help keep the lungs clean by moving a film of debris-trapping mucus upward.Figure 1.16
  39. 39. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.4: Evolution accounts for life’s unity and diversity • The history of life – Is a saga of a changing Earth billions of years old Figure 1.17
  40. 40. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The evolutionary view of life – Came into sharp focus in 1859 when Charles Darwin published On the Origin of Species by Natural Selection Figure 1.18
  41. 41. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The Origin of Species articulated two main points – Descent with modification – Natural selection Figure 1.19
  42. 42. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Natural Selection • Darwin proposed natural selection – As the mechanism for evolutionary adaptation of populations to their environments Population of organisms Hereditary variations Differences in reproductive success Evolution of adaptations in the population Overproduction and struggle for existence Figure 1.20
  43. 43. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Natural selection is the evolutionary process that occurs – When a population’s heritable variations are exposed to environmental factors that favor the reproductive success of some individuals over others 1 Populations with varied inherited traits 2 Elimination of individuals with certain traits. 3 Reproduction of survivors. 4 Increasing frequency of traits that enhance survival and reproductive success.Figure 1.21
  44. 44. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • The products of natural selection – Are often exquisite adaptations of organisms to the special circumstances of their way of life and their environment Figure 1.22
  45. 45. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Tree of Life • Many related organisms – Have very similar anatomical features, adapted for their specific ways of life • Such examples of kinship – Connect life’s “unity in diversity” to Darwin’s concept of “descent with modification”
  46. 46. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Darwin proposed that natural selection – Could enable an ancestral species to “split” into two or more descendant species, resulting in a “tree of life” Large ground finch Small ground finch Geospiza magnirostris Seed eater Sharp-beaked ground finch Camarhynchus psitacula Green warbler finch Large tree finchLarge cactus ground finch Ground finches Tree finches Insect eaters Bud eater Warbler finches Common ancestor from South American mainland Gray warbler finch Certhidea olivacea Certhidea fusca Geospiza difficilis Cactus flower eater Geospiza scandens Seed eater Geospiza conirostris Geospiza fortis Medium ground finch Geospiza fuliginosa Mangrove finch Cactospiza heliobates Cactospiza pallida Woodpecker finch Medium tree finch Camarhynchus pauper Small tree finch Vegetarian finch Camarhynchus parvulus Platyspiza crassirostris Cactus ground finch Figure 1.23
  47. 47. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Each species is on twig of a branching tree of life – Extending back in time through ancestral species more and more remote • All of life – Is connected through its long evolutionary history
  48. 48. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.5: Biologists use various forms of inquiry to explore life • At the heart of science is inquiry – A search for information and explanation, often focusing on specific questions • Biology blends two main processes of scientific inquiry – Discovery science – Hypothesis-based science
  49. 49. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Discovery Science • Discovery science – Describes natural structures and processes as accurately as possible through careful observation and analysis of data
  50. 50. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Types of Data • Data – Are recorded observations – Can be quantitative or qualitative Figure 1.24
  51. 51. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Induction in Discovery Science • In inductive reasoning – Scientists derive generalizations based on a large number of specific observations
  52. 52. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Hypothesis-Based Science • In science, inquiry that asks specific questions – Usually involves the proposing and testing of hypothetical explanations, or hypotheses
  53. 53. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Role of Hypotheses in Inquiry • In science, a hypothesis – Is a tentative answer to a well-framed question, an explanation on trial – Makes predictions that can be tested
  54. 54. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • We all use hypotheses in solving everyday problems Observations Questions Hypothesis # 1: Dead batteries Hypothesis # 2: Burnt-out bulb Prediction: Replacing batteries will fix problem Prediction: Replacing bulb will fix problem Test prediction Test does not falsify hypothesis Test prediction Test falsifies hypothesisFigure 1.25
  55. 55. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Deduction: The “If…then” Logic of Hypothesis-Based Science • In deductive reasoning – The logic flows from the general to the specific • If a hypothesis is correct – Then we can expect a particular outcome
  56. 56. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings A Closer Look at Hypotheses in Scientific Inquiry • A scientific hypothesis must have two important qualities – It must be testable – It must be falsifiable
  57. 57. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Myth of the Scientific Method • The scientific method – Is an idealized process of inquiry • Very few scientific inquiries – Adhere to the “textbook” scientific method
  58. 58. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • In mimicry – A harmless species resembles a harmful species Flower fly (non-stinging) Honeybee (stinging) Figure 1.26 A Case Study in Scientific Inquiry: Investigating Mimicry in Snake Populations
  59. 59. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • In this case study – Mimicry in king snakes is examined – The hypothesis predicts that predators in non–coral snake areas will attack king snakes more frequently than will predators that live where coral snakes are present Scarlet king snake Scarlet king snake Key Range of scarlet king snake Range of eastern color snake Eastern coral snake North Carolina South Carolina Figure 1.27
  60. 60. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Field Experiments with Artificial Snakes • To test this mimicry hypothesis – Researchers made hundreds of artificial snakes, an experimental group resembling king snakes and a control group of plain brown snakes (a) Artificial king snake (b) Brown artificial snake that has been attackedFigure 1.28
  61. 61. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • After a given period of time – The researchers collected data that fit a key prediction Figure 1.29 In areas where coral snakes were present, most attacks were on artificial king snakes Key % of attacks on artificial king snakes % of attacks on brown artificial snakes Field site with artificial snakes 17% 83% North Carolina South Carolina X X X X X XX XX X XX XX In areas where coral snakes were absent, most attacks were on artificial king snakes 84% 16% Key
  62. 62. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Designing Controlled Experiments • Experiments must be designed to test – The effect of one variable by testing control groups and experimental groups in a way that cancels the effects of unwanted variables
  63. 63. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Limitations of Science • Science cannot address supernatural phenomena – Because hypotheses must be testable and falsifiable and experimental results must be repeatable
  64. 64. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Theories in Science • A scientific theory – Is broad in scope – Generates new hypotheses – Is supported by a large body of evidence
  65. 65. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Model Building in Science • Models of ideas, structures, and processes – Help us understand scientific phenomena and make predictions To lungs To body Right artium Right artium Right ventricle Right ventricle From lungs From body Figure 1.30
  66. 66. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings The Culture of Science • Science is a social activity – Characterized by both cooperation and competition Figure 1.31
  67. 67. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Science, Technology, and Society • Technology – Applies scientific knowledge for some specific purpose Figure 1.32
  68. 68. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Concept 1.6: A set of themes connects the concepts of biology • Underlying themes – Provide a framework for understanding biology
  69. 69. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings • Eleven themes that unify biology Table 1.1

×