1. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings PowerPoint ® Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp Introduction: Themes in the Study of Life Chapter 1

2. csmithbio.wikispaces.com

3. Biology ….. the scientific study of life

4. How do we define life? Life defies a simple, one-sentence definition Life is recognized by what living things do Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

5. Order Evolutionary adaptation Response to the environment Reproduction Growth and development Energy processing Regulation Fig. 1-3

6. Themes help to organize biological information. The Overarching Theme of Biology is EVOLUTION! Evolution makes sense of everything we know about living organisms Organisms living on Earth are modified descendents of common ancestors Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

7. Fig. 1-4 The biosphere Communities Populations Organisms Ecosystems Organs and organ systems Cells Cell Organelles Atoms Molecules Tissues 10 µm 1 µm 50 µm The study of life can be divided into different levels of biological organization

8. Emergent Properties New properties emerge at each level in the biological hierarchy Emergent properties result from the arrangement and interaction of parts within a system Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

9. The Power and Limitations of Reductionism Reductionism is the reduction of complex systems to simpler components that are more manageable to study – For example, the molecular structure of DNA

10. But to understand how DNA functions, we have to look at the parts together…..emergent property approach

11. Systems Biology A system is a combination of components that function together Systems biology constructs models for the dynamic behavior of whole biological systems The systems approach poses questions such as: – How does a drug for blood pressure affect other organs? – How does increasing CO 2 alter the biosphere?

12. Theme: Organisms interact with their environments, exchanging matter and energy Every organism interacts with its environment, including nonliving factors and other organisms Energy exchange between an organism and its environment often involves energy transformations Energy flows through an ecosystem, usually entering as light and exiting as heat Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

13. Fig. 1-5 Sunlight Ecosystem Heat Cycling of chemical nutrients Producers (plants and other photosynthetic organisms) Chemical energy Consumers (such as animals)

14. Theme: Structure and function are correlated at all levels of biological organization Structure and function of living organisms are closely related – For example, a leaf is thin and flat, maximizing the capture of light by chloroplasts Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

15. (a) Wings (c) Neurons (b) Bones Infoldings of membrane Mitochondrion (d) Mitochondria 0.5 µm 100 µm Fig. 1-6

16. Theme: Cells are an organism’s basic units of structure and function The cell is the lowest level of organization that can perform all activities required for life All cells: – Are enclosed by a membrane – Use DNA as their genetic information The ability of cells to divide is the basis of all reproduction, growth, and repair of multicellular organisms Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

17. 25 µm Fig. 1-7

18. A eukaryotic cell has membrane-enclosed organelles, the largest of which is usually the nucleus By comparison, a prokaryotic cell is simpler and usually smaller, and does not contain a nucleus or other membrane-enclosed organelles Bacteria and Archaea are prokaryotic; plants, animals, fungi, and all other forms of life are eukaryotic

19. 1 µm Organelles Nucleus (contains DNA) Cytoplasm Membrane DNA (no nucleus) Membrane Eukaryotic cell Prokaryotic cell Fig. 1-8

20. Prokaryotic or eukaryotic?

21. Theme: The continuity of life is based on heritable information in the form of DNA Chromosomes contain most of a cell’s genetic material in the form of DNA (deoxyribonucleic acid) DNA is the substance of genes Genes are the units of inheritance that transmit information from parents to offspring Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

22. Fig. 1-10 Nucleus DNA Cell Nucleotide (a) DNA double helix(b) Single strand of DNA

23. The sequence of nucleotides in a DNA molecule dictate what proteins or RNA will be made. An organism’s genome is its entire set of genetic instructions Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

24. Systems Biology at the Levels of Cells and Molecules The human genome and those of many other organisms have been sequenced using DNA- sequencing machines Knowledge of a cell’s genes and proteins can be integrated using a systems approach – Bioinformatics, which is the use of computational tools to process a large volume of data Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

25. Fig. 1-11 Advance technology is used to decipher genomes.

26. Theme: Feedback mechanisms regulate biological systems Feedback mechanisms allow biological processes to self-regulate Negative feedback means that as more of a product accumulates, the process that creates it slows and less of the product is produced Positive feedback means that as more of a product accumulates, the process that creates it speeds up and more of the product is produced Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

27. Fig. 1-13 Negative feedback  Excess D blocks a step D D D A B C Enzyme 1 Enzyme 2 Enzyme 3 D (a) Negative feedback W Enzyme 4 X Positive feedback Enzyme 5 Y + Enzyme 6 Excess Z stimulates a step Z Z Z Z (b) Positive feedback Negative – more product Slows down process Positive - More product speeds up process

28. Fig. 1-13a Excess D blocks a step (a) Negative feedback Negative feedback D D D D C B A Enzyme 1 Enzyme 2 Enzyme 3 –

29. Fig. 1-13b Excess Z stimulates a step (b) Positive feedback Z Positive feedback Enzyme 4 Enzyme 5 Enzyme 6 Z Z Z Y X W +

30. Evolution accounts for the unity and diversity of life “Nothing in biology makes sense except in the light of evolution”—Theodosius Dobzhansky Evolution unifies biology at different scales of size throughout the history of life on Earth Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

31. Grouping Species: The Basic Idea Taxonomy is the branch of biology that names and classifies species into groups of increasing breadth Domains, followed by kingdoms, are the broadest units of classification Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

32. Fig. 1-14 SpeciesGenusFamilyOrderClassPhylumKingdomDomain Ursus americanus (American black bear) Ursus Ursidae Carnivora Mammalia Chordata Animalia Eukarya

33. The Three Domains of Life The three-domain system is currently used, and replaces the old five-kingdom system Domain Bacteria and domain Archaea comprise the prokaryotes Domain Eukarya includes all eukaryotic organisms Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

34. Fig. 1-15 (a) DOMAIN BACTERIA (b) DOMAIN ARCHAEA (c) DOMAIN EUKARYA Protists Kingdom Fungi Kingdom Plantae Kingdom Animalia

35. The domain Eukarya includes three multicellular kingdoms: – Plantae – Fungi – Animalia Other eukaryotic organisms were formerly grouped into a kingdom called Protista, though these are now often grouped into many separate kingdoms Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

36. Fig. 1-15c (c) DOMAIN EUKARYA Protists Kingdom Fungi Kingdom Plantae Kingdom Animalia

37. Unity in the Diversity of Life A striking unity underlies the diversity of life; for example: – DNA is the universal genetic language common to all organisms – Unity is evident in many features of cell structure Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

38. Fig. 1-16 Cilia of Paramecium Cross section of a cilium, as viewed with an electron microscope Cilia of windpipe cells 15 µm 5 µm 0.1 µm

39. Charles Darwin and the Theory of Natural Selection Charles Darwin published On the Origin of Species by Means of Natural Selection in 1859 Darwin made two main points: – Species showed evidence of “descent with modification” from common ancestors – Natural selection is the mechanism behind “descent with modification”

40. Darwin observed that: – Individuals in a population have traits that vary – Many of these traits are heritable (passed from parents to offspring) – More offspring are produced than survive – Competition is inevitable – Species generally suit their environment

41. Darwin inferred that: – Individuals that are best suited to their environment are more likely to survive and reproduce – Over time, more individuals in a population will have the advantageous traits In other words, the natural environment “selects” for beneficial traits Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

42. Fig. 1-20 Population with varied inherited traits. Elimination of individuals with certain traits. Reproduction of survivors. Increasing frequency of traits that enhance survival and reproductive success. 43 21

43. The Tree of Life “Unity in diversity” arises from “descent with modification” Fossils provide additional evidence of anatomical unity from descent with modification Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

44. Fig. 1-22 COMMON ANCESTOR Warbler finches Insect-eaters Seed-eater Bud-eater Insect-eatersTree finches Green warbler finch Certhidea olivacea Gray warbler finch Certhidea fusca Sharp-beaked ground finch Geospiza difficilis Vegetarian finch Platyspiza crassirostris Mangrove finch Cactospiza heliobates Woodpecker finch Cactospiza pallida Medium tree finch Camarhynchus pauper Large tree finch Camarhynchus psittacula Small tree finch Camarhynchus parvulus Large cactus ground finch Geospiza conirostris Cactus ground finch Geospiza scandens Small ground finch Geospiza fuliginosa Medium ground finch Geospiza fortis Large ground finch Geospiza magnirostris Ground finches Seed-eaters Cactus-flower- eaters Evolutionary relationships are often illustrated with tree-like diagrams that show ancestors and their descendents

45. Scientists use two main forms of inquiry in their study of nature The word Science is derived from Latin and means “to know” Inquiry is the search for information and explanation There are two main types of scientific inquiry: discovery science and hypothesis- based science Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

46. Discovery Science Discovery science describes natural structures and processes This approach is based on observation and the analysis of data Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

47. Types of Data Data are recorded observations or items of information Data fall into two categories – Qualitative, or descriptions rather than measurements – Quantitative, or recorded measurements, which are sometimes organized into tables and graphs Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

48. Fig. 1-23

49. Induction in Discovery Science Inductive reasoning draws conclusions through the logical process of induction Repeat specific observations can lead to important generalizations – For example, “Organisms are made of cells.” – Inductive = generalizing Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

50. Hypothesis-Based Science Observations can lead us to ask questions and propose hypothetical explanations called hypotheses A hypothesis is a tentative answer to a well- framed question Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

51. The Role of Hypotheses in Inquiry A scientific hypothesis leads to predictions that can be tested by observation or experimentation A hypothesis must be testable and falsifiable Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

52. Variables Independent: What is changed in the experiment Dependent: What is measured INDEPENDENT – MANIPULATED DEPENDENT - MEASURED

53. Theories in Science In the context of science, a theory is: – Broader in scope than a hypothesis – General, and can lead to new testable hypotheses – Supported by a large body of evidence in comparison to a hypothesis Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

54. Deduction: The “If…Then” Logic of Hypothesis Based Science Deductive reasoning uses general premises to make specific predictions For example, if organisms are made of cells (premise 1), and humans are organisms (premise 2), then humans are composed of cells (deductive prediction) Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

55. Inductive Reasoning Deriving generalizations from a large number of specific observations. Living things are made of cells.

56. The Myth of the Scientific Method The scientific method is an idealized process of inquiry Hypothesis-based science is based on the “textbook” scientific method but rarely follows all the ordered steps Discovery science has made important contributions with very little dependence on the so-called scientific method Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

57. Designing Controlled Experiments A controlled experiment compares an experimental group with a control group Ideally, only the variable of interest differs between the control and experimental groups A controlled experiment does not mean that all unwanted variables are kept constant Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

58. Is Shubin’s research on fossils a discovery science or hypothesis-based science?

59. Limitations of Science Science only deals with the observable or testable. Science cannot support or falsify supernatural explanations, which are outside the bounds of science Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings

60. Fig. 1-29

61. Types of graphs Line graphs are used to display data or information that changes continuously over time. Line graphs allow us to see overall trends such as an increase or decrease in data over time.

62. Bar graphs are used to compare facts. The bars provide a visual display for comparing quantities in different categories or groups. Bar graphs help us to see relationships quickly. However, bar graphs can be difficult to read accurately. A change in the scale in a bar graph may alter one's visual perception of the data.

63. Circle Graphs are used to compare the parts of a whole, Circle graphs are best used for displaying data when there are no more than five or six sectors, and when the values of each sector are different. Otherwise they can be difficult to read and understand.

64. Scatter plots are similar to line graphs in that they start with mapping quantitative data points. The difference is that with a scatter plot, the decision is made that the individual points should not be connected directly together with a line but, instead express a trend.

65. Scatter Plot

66. You can use a line of best fit to see a trend in the data.