1. © 2010 Pearson Education, Inc. Lectures by Chris C. Romero, updated by Edward J. Zalisko PowerPoint ® Lectures for Campbell Essential Biology, Fourth Edition – Eric Simon, Jane Reece, and Jean Dickey Campbell Essential Biology with Physiology, Third Edition – Eric Simon, Jane Reece, and Jean Dickey Chapter 1 Introduction: Biology Today

2. © 2010 Pearson Education, Inc. Derived from Greek words: Life Study of Biology is the scientific study of life and living organisms. The study of biology encompasses –a wide scale of size and –a huge variety of life, both past and present. What is Biology ? © 2013 Pearson Education, Inc.

3. We are living in a golden age of biology. Biology provides exciting breakthroughs changing our culture. –Molecular biology is solving crimes and revealing ancestries. –Ecology helps us address environmental issues such as the causes and consequences of global climate changes –Neuroscience and evolutionary biology are reshaping psychology and sociology. Biology is the scientific study of life. –Life is structured on a size scale ranging from the molecular to the global. –Biology’s scope stretches across the enormous diversity of life on Earth. © 2010 Pearson Education, Inc. Biology and Society: Biology All Around Us

4. © 2010 Pearson Education, Inc. What is Life Life can not be explained in a simple, one- sentence definition Life is recognized by what living things do Life has properties and processes

5. © 2010 Pearson Education, Inc. 1)Order (Cells and organization) 2)Regulation and homeostasis 3)Growth and development 4)Energy utilization 5)Response to environmental changes 6)Reproduction 7)Biological evolution The Properties of Life

6. © 2010 Pearson Education, Inc. Figure 1.1ba a) Order: All living things exhibit complex but ordered organization, as seen in the structure of a pinecone. Figure 1.1bb b) Regulation and Homeostasis: The environment outside an organism may change drastically, but the organism can adjust its internal environment, within limits.

7. © 2010 Pearson Education, Inc. Figure 1.1bc Figure 1.1bd c) Growth and Development: Information carried by genes controls the pattern of growth and development. d) Energy Utilization: Organisms take in energy and use to perform all of life’s activities.

8. © 2010 Pearson Education, Inc. Figure 1.1be e) Response to the Environment: All organisms respond to environmental stimuli.

9. © 2010 Pearson Education, Inc. Figure 1.1bf f) Reproduction: Organisms reproduce their own kind. Figure 1.1bg g) Evolution: Reproduction underlies the capacity of populations to change (evolve) over time. Evolutionary change has been a central, unifying feature of life since life arose nearly 4 billion years ago.

10. © 2010 Pearson Education, Inc. Life at Its Many Levels Biologists explore life at levels ranging from the biosphere to the molecules that make up cells. Biosphere: consists of all the environments on Earth that support life. It takes many molecules to build a cell, many cells to make a tissue, multiple tissues to make an organ etc. At each new level, novel properties emerge, properties that were not part of the components of the preceding level. The whole is greater than the sum of its parts. We’ll take a closer look at two biological levels near opposite ends of the size scale: ecosystems and cells.

11. © 2010 Pearson Education, Inc. Figure 1.2-3 Organisms 5 1 2 3 4 7 6 8 10 9 Biosphere Ecosystems Populations Communities Organ Systems and Organs Tissues Cells Organelles Molecules and Atoms Nucleus Atom

12. © 2010 Pearson Education, Inc. Figure 1.2a 1 Biosphere

13. © 2010 Pearson Education, Inc. Figure 1.2b 2 3 Ecosystems Communities An Ecosystem consist of -all the living things in a particular area -All nonliving physical components that affect the organisms (soil, water) A Community encompasses all the organisms in the area

14. © 2010 Pearson Education, Inc. Figure 1.2c Organisms 5 4 Populations A Population consists of interbreeding organisms of the same species such as the iguanas An Organism is at the individual level and it is made of the organ systems

15. © 2010 Pearson Education, Inc. Figure 1.2d 6 Organ Systems and Organs An Organism’s body consists of several organ systems, each of which contains two or more organs. The iguana’s circulatory system include its heart and blood vessels.

16. © 2010 Pearson Education, Inc. Figure 1.2e 7 Tissues Each organ is made up of several different tissues such as the heart muscle shown here. A tissue consists of group of similar cells performing a specific function.

17. © 2010 Pearson Education, Inc. Figure 1.2f 8 9 Cells Organelles Nucleus A cell is a smallest unit that can display all the characteristics of life Organelles are functional components of cells such as the nucleus that houses the DNA

18. © 2010 Pearson Education, Inc. Figure 1.2g 10 Molecules and Atoms Atom Molecules are clustered of smaller chemical units called atoms. DNA is the molecule of inheritance and the substance of the genes. Each sphere represents a single atom.

19. © 2010 Pearson Education, Inc. 1) Atoms 2) Molecules and macromolecules 3) Organelles 4) Cells 5) Tissues 6) Organs 7) Organism 8) Population 9) Community 10) Ecosystem 11) Biosphere Life at many levels

20. © 2010 Pearson Education, Inc. Ecosystems Each organism interacts continuously with its environment. –Organisms interact continuously with the living (biotic) and nonliving (abiotic) factors in the environment. –All the living organisms in a specific area, along with all of the nonliving factors with which they interact, form an ecosystem. © 2013 Pearson Education, Inc.

21. © 2010 Pearson Education, Inc. Ecosystems The dynamics of any ecosystem depend on two main processes: –recycling of chemical nutrients and –flow of energy. Within ecosystems –nutrients are recycled but –energy flows through. © 2013 Pearson Education, Inc.

22. © 2010 Pearson Education, Inc. ECOSYSTEM Inflow of light energy Outflow of heat energy Producers (plants and other photosynthetic organisms) Chemical energy (food) Cycling of nutrients Consumers (animals) Decomposers (in soil) Figure 1.3 Nutrient and energy flow in an ecosystem

23. © 2010 Pearson Education, Inc. Cells and Their DNA Cells are the lowest level of structure that can perform all activities required for life. –All organisms are composed of cells. Cells are the subunits that make up multicellular organisms such as humans and trees. All cells share many characteristics. –All cells are enclosed by a membrane that regulates the passage of materials between the cell and its surroundings. –Every cell uses DNA as its genetic information. © 2013 Pearson Education, Inc.

24. © 2010 Pearson Education, Inc. We can distinguish two major types of cells: The prokaryotic cell is –simpler and usually smaller and –characteristic of bacteria. The eukaryotic cell is larger, more complex, and –subdivided by internal membranes into different functional compartments called organelles and –contains MEMBRANE-ENCLOSED nucleus and –the nucleus is the largest organelle in most eukaryotic cells –found in plants and animals. Cells and Their DNA © 2013 Pearson Education, Inc.

25. © 2010 Pearson Education, Inc. Figure 1.4 Nucleoid region Nucleus Organelles Prokaryotic cell (bacterium) Smaller Simpler structure DNA concentrated in nucleoid region, which is not enclosed by membrane Lacks most organelles Larger More complex structure Nucleus enclosed by membrane Contains many types of organelles Eukaryotic cell Colorized TEM Two main kinds of cells: prokaryotic and eukaryotic

26. © 2010 Pearson Education, Inc. All cells use DNA as the chemical material of genes. –Genes are the units of inheritance that transmit information from parents to offspring. The language of DNA –is common to all organisms and –contains just four letters A, G, C, T The entire book of genetic instructions that an organism inherits is called its genome. An average-sized gene may be hundreds or thousands of chemical “letters” long. The nucleus of each human cell packs a genome that is about 3 billion chemical letters long. The language of DNA

27. © 2010 Pearson Education, Inc. Figure 1.5 A DNA molecule The four chemical building blocks of DNA

28. © 2010 Pearson Education, Inc. Genetic engineering and biotechnology have allowed us to manipulate the DNA and genes of organisms. Bacteria can make insulin because a gene for insulin production was transplanted into their DNA. DNA technology in the Drug Industry

29. © 2010 Pearson Education, Inc. Life in Its Diverse Forms Diversity is the hallmark of life. –The diversity of known life includes 1.8 million species. –Estimates of the total diversity range from 10 million to over 100 million species.

30. © 2010 Pearson Education, Inc. Grouping Species: The Basic Concept Biodiversity can be beautiful but overwhelming. Taxonomy is the branch of biology that names and classifies species. –It formalizes the hierarchical ordering of organisms. The three domains of life are –Bacteria –Archaea –Eukarya Bacteria and Archaea (prokaryotic cells); Eukarya (eukaryotic cells).

31. © 2010 Pearson Education, Inc. Figure 1.8 Protists (multiple kingdoms) Kingdom Animalia Kingdom Fungi Kingdom Plantae DOMAIN EUKARYA DOMAIN ARCHAEA DOMAIN BACTERIA

32. © 2010 Pearson Education, Inc. Figure 1.8a DOMAIN ARCHAEA DOMAIN BACTERIA Bacteria and Archaea have prokaryotic cells

33. © 2010 Pearson Education, Inc. Eukarya includes Kingdom Plantae Kingdom Fungi Kingdom Animalia Protists (multiple kingdoms) Protists are generally single celled. Most plants, fungi, and animals are multicellular Kingdom Plantae Kingdom Fungi Kingdom Animalia Protists  multiple kingdoms  LM Domain Eukarya

34. © 2010 Pearson Education, Inc. These three multicellular kingdoms are distinguished by how they obtain food. –Plants produce their own sugars and other foods by photosynthesis. –Fungi are mostly decomposers, digesting dead organisms. –Animals obtain food by eating and digesting other organisms. Mode of Nutrition

35. Match the following description to its most likely domain and/or kingdom a. A foot-tall organism capable of producing its own food from sunlight 1.Bacteria b. A microscopic, simple, nucleus- free organism found growing in a riverbed 2. Eukarya/Animalia c. An inch-tall organism growing on the forest floor that consumes material from dead leaves 3. Eukarya/fungi d. A thimble-sized organism that feeds on algae growing in a pond 4. Eukarya/Plantae Test Yourself

36. © 2010 Pearson Education, Inc. Unity in the Diversity of Life  Diverse forms of life in diverse environments –how, in adapting to their environments, organisms have developed different traits  Underlying the diversity of life is a striking unity, especially at the lower levels of structure. –For example, all life uses the genetic language of DNA.  All life displays a common set of characteristics –all organisms have the same types of DNA molecules –many seemingly unrelated organisms share similar features  Biological evolution accounts for this combination of unity and diversity.

37. © 2010 Pearson Education, Inc. Life evolves. –Each species is one twig of a branching tree of life extending back in time through ancestral species more and more remote. –Species that are very similar, such as the brown bear and polar bear, share a more recent common ancestor. EVOLUTION: BIOLOGY’S UNIFYING THEME © 2013 Pearson Education, Inc.

38. © 2010 Pearson Education, Inc. Figure 1.10 Millions of years ago Giant panda Common ancestor of polar bear and brown bear 20 25 1015305 Common ancestor of all modern bears Ancestral bear Spectacled bear Sloth bear Sun bear American black bear Asiatic black bear Polar bear Brown bear

39. © 2010 Pearson Education, Inc. The Darwinian View of Life The evolutionary view of life came into focus in 1859 when Charles Darwin published The Origin of Species. Darwin’s book developed two main points: –Descent with modification –Natural selection

40. © 2010 Pearson Education, Inc. Natural Selection Darwin was struck by the diversity of animals on the Galápagos Islands. He thought that adaptation to the environment and the origin of new species were closely related processes. –As populations separated by a geographic barrier adapted to local environments, they became separate species. Darwin synthesized the theory of natural selection from two observations

41. © 2010 Pearson Education, Inc. Observation 1: Overproduction and competition Observation 2: Individual variation Conclusion: Unequal reproductive success –It is this unequal reproductive success that Darwin called natural selection. –The product is adaptation, the accumulation of favorable variation in a population over time –Example, fur color in polar and brown bear Darwin’s Inescapable Conclusion

42. © 2010 Pearson Education, Inc. Population with varied inherited traits. Initially, the pop. varies extensively in the coloration of ind. beetles, from light gray to charcoal. Elimination of individuals with certain traits. For hungry birds that prey on beetles, it is easiest to spot the beetles that are lightest in color. Reproduction of survivors. The selective predation favors survival and reproduction success of the darker beetles. Thus, genes for the dark color are passed along to next gen. in greater frequency. Increasing frequency of traits that enhance survival and reproductive success. Generation after gen., the beetles pop. adapts to its environment through natural selection. Figure 1.12

43. © 2010 Pearson Education, Inc. Observing Artificial Selection Artificial selection is the selective breeding of domesticated plants and animals by humans. In artificial selection, humans do the selecting instead of the environment.  a  Vegetables descended from wild mustard Cabbage from terminal bud Brussels sprouts from lateral buds Kohlrabi from stem Kale from leavesBroccoli from flower and stems Cauliflower from flower clusters Wild mustard

44. © 2010 Pearson Education, Inc. Figure 1.13b (b) Domesticated dogs descended from wolves Domesticated dogsGray wolves

45. © 2010 Pearson Education, Inc. THE PROCESS OF SCIENCE The word science is derived from Latin verb meaning “to know.” –Science is a way of knowing. –Science developed from people’s curiosity about themselves and the world around them. Discovery Science Enables us to describe life at its many levels. Verifiable observations and measurements are the data of discovery science. Discovery science can lead to important conclusions based on a type of logic called inductive reasoning. An inductive conclusion is a generalization that summarizes many concurrent observations. –Example all organisms are made of cells

46. © 2010 Pearson Education, Inc. Figure 1.14a

47. © 2010 Pearson Education, Inc. Hypothesis-Driven Science The scientific method consists of a series of steps. –The key element of the scientific method is hypothesis- driven science. A hypothesis is a proposed explanation for a set of observations—an idea on trial. Once a hypothesis is formed, an investigator can use deductive logic to test it. –In deduction, the reasoning flows from general to specific. In the process of science, the deduction usually takes the form of predictions about experimental results. –Then the hypothesis is tested by performing an experiment to see whether results are as predicted. –This deductive reasoning takes the form of “If…then” logic.

48. © 2010 Pearson Education, Inc. Figure 1.15-1 Observation The remote doesn’t work. Hypothesis The batteries are dead. Question What’s wrong? Prediction With new batteries, it will work. Applying the scientific method to a common problem

49. © 2010 Pearson Education, Inc. Figure 1.15-2 Experiment supports hypothesis; make more predictions and test. Observation The remote doesn’t work. Hypothesis The batteries are dead. Question What’s wrong? Experiment Replace batteries. Prediction With new batteries, it will work.

50. © 2010 Pearson Education, Inc. Figure 1.15-3 Experiment does not support hypothesis. Experiment supports hypothesis; make more predictions and test. Observation The remote doesn’t work. Hypothesis The batteries are dead. Question What’s wrong? Experiment Replace batteries. Prediction With new batteries, it will work. Revise.

51. © 2010 Pearson Education, Inc. If you are sitting in HCCS cafeteria and watching how many students are eating pizza or burger during lunch time, what kind of science are you performing? If you come up with a tentative explanation for their dietary behavior and then test your idea, what kind of science you are performing? Test Yourself

52. The Process of Science: Are Trans Fats Bad for You? Case study is an in-depth examination of an actual investigation. Dietary fat comes in different forms. Trans fat is a non-natural form produced through manufacturing processes. Trans fat –Adds texture –Increases shelf life –Is inexpensive to prepare A study of 120,000 female nurses found that high levels of trans fat nearly doubled the risk of heart disease. © 2010 Pearson Education, Inc.

53. A hypothesis-driven study published in 2004 –Started with the observation that human body fat (adipose tissue) retains traces of consumed dietary fat. –Asked the question: Would the adipose tissue of heart attack patients be different from a similar group of healthy patients? –Formed the hypothesis that it would be – predicted that healthy patients’ body fat would contain less trans fat than the body fat in heart attack victims. The Process of Science: Are Trans Fats Bad for You?

54. © 2010 Pearson Education, Inc. The researchers set up an experiment to determine the amounts of fat in the adipose tissue of 79 patients who had a heart attack. They compared these patients to the data for 167 patients who had not had a heart attack. This is an example of a controlled experiment, in which the control and experimental groups differ only in one variable—the occurrence of a heart attack. The results showed significantly higher levels of trans fat in the bodies of the heart attack patients. The Process of Science: Are Trans Fats Bad for You?

55. © 2010 Pearson Education, Inc. Figure 1.16 Heart attack patients 1.77 Control group 1.48 2.0 1.5 1.0 0.5 0 Trans fats in adipose tissue (g trans fat per 100 g total fat)

56. © 2010 Pearson Education, Inc. Theories in Science What is a scientific theory, and how is it different from a hypothesis? –A theory is much broader in scope than a hypothesis. –Theories only become widely accepted in science if they are supported by an accumulation of extensive and varied evidence. For example Hypothesis: “white fur is an evolutionary adaptation that helps polar bears survive in an arctic habitat”. Theory: “Adaptations evolve by natural selection”

57. © 2010 Pearson Education, Inc. The Culture of Science Scientists build on what has been learned from earlier research. –They pay close attention to contemporary scientists working on the same problem. Cooperation and competition characterize the scientific culture. –Scientists check the conclusions of others by attempting to repeat experiments. –Scientists are generally skeptics. Science has two key features that distinguish it from other forms of inquiry. Science –depends on observations and measurements that others can verify and –requires that ideas (hypotheses) are testable by experiments that others can repeat. © 2013 Pearson Education, Inc.

58. © 2010 Pearson Education, Inc. Science, Technology, and Society Science and technology are interdependent. –New technologies advance science. –Scientific discoveries lead to new technologies. –For example, the discovery of the structure of DNA about 60 years ago led to a variety of DNA technologies. –Technology has improved our standard of living in many ways, but it is a double-edged sword. –Technology that keeps people healthier has enabled the human population to double to 7 billion in just the past 40 years. –The environmental consequences of this population growth may be devastating. © 2013 Pearson Education, Inc.

59. © 2010 Pearson Education, Inc. Evolution Connection: Evolution in Our Everyday Lives Antibiotics are drugs that help cure bacterial infections. When an antibiotic is taken, most bacteria are typically killed. Those bacteria most naturally resistant to the drug can still survive. Those few resistant bacteria can soon multiply and become the norm and not the exception. The evolution of antibiotic-resistant bacteria is a huge problem in public health. Antibiotics are being used more selectively. Many farmers are reducing the use of antibiotics in animal feed. © 2013 Pearson Education, Inc.

60. © 2010 Pearson Education, Inc. It is important to note that the adaptation of bacteria to an environment containing an antibiotic does not mean that the drug created the antibiotic resistance. Instead, the environment screened the heritable variations that already existed among the existing bacteria. Evolution Connection: Evolution in Our Everyday Lives © 2013 Pearson Education, Inc.