1. Chapter 1 Exploring Life Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

2. Images : Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings HIGHLY ORDERED

3. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings EVOLUTIONARY ADAPTATION

4. Image from: http://vilenski.org/science/safari/cellstructure/chloroplasts.htm Venus fly trap © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Image from: http://www.travel-net.com/~andrews/images/animations/traffic.gif RESPOND TO ENVIRONMENT

5. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings REGULATION Living things adjust and control cell processes to maintain conditions suitable for life HOMEOSTASIS

6. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings ENERGY PROCESSING

7. Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings GROWTH & DEVELOPMENT

8. Images: Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings Planaria animation: http://www.t3.rim.or.jp/~hylas/planaria/title.htm REPRODUCTION

9. Ecosystems Communities Organisms Populations Biosphere A Hierarchy of Biological Organization

10. 8 Cells 6 Organs and organ systems 7 Tissues 10 Molecules 9 Organelles 50 µm 10 µm 1 µm Atoms

11. New properties emerge with each step up in hierarchy of biological order Structural arrangement and interaction of parts is important to function! http://www.animationlibrary.com/sc/101/Bicycling/?page=1http://www.cartoonstock.com/lowres/jmc0030l.jpg

12. Unifying Themes in Biology connect concepts & provide framework for understanding Evolution ~ biology’s core theme; differential reproductive success Emergent Properties ~ the sum is greater than the parts The Cell ~ basic structure of all organisms Heritable Information ~ DNA Structure & Function ~ form follows function Environmental Interaction ~ organisms are open systems Energy and life ~ work requires energy that flows from sunlight to producers to consumers Regulation ~ feedback mechanisms Unity & Diversity ~ universal genetic code Scientific Inquiry ~ observation; testing; repeatability Science, Technology & Society ~ functions of our world

13. In feedback regulation – The output, or product, of a process regulates that very process http://www.wildtech.org/images/feedback.gif

14. In negative feedback – An accumulation of an end product slows the process that produces that product B A C D Enzyme 1 Enzyme 2 Enzyme 3 D D D D D D D D DD C B A Negative feedback Example: sugar breakdown generates ATP; excess ATP inhibits an enzyme near the beginning of the pathway

15. In positive feedback (less common) – The end product speeds up production WW X Y Z Z Z Z Z Z Z Z Z Z Z ZZ Z ZZ Z Z Z Y X Enzyme 4 Enzyme 5 Enzyme 6 Enzyme 4 Enzyme 5 Enzyme 6 Positive feedback EXAMPLE: Chemicals released by platelets that accumulate at injury site, attract MORE platelets to the site.

16. 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

17. Discovery science – Describes natural structures and processes as accurately as possible through careful observation and analysis of data Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

18. Types of Data DATA are recorded observations Can be: – Quantitative involves analysis of numerical data (measure, count, etc) – Qualitative involves analysis of data such as words (e.g., from interviews), pictures (e.g., video), or objects (e.g., an artifact). http://www.3g.co.uk/PR/August2006/Casio.jpg http://www.bio-world.com/images/042135.jpg http://plus.maths.org/latestnews/may-aug05/millionaire/measure.jpg Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

19. Induction in Discovery Science In inductive reasoning – Scientists derive generalizations based on a large number of specific observations EX: “The sun always rises in the East.” “All living things are made of cells.” http://virtualbible.net/literature/firstprinciples/Inductive.jpg

20. Hypothesis-Based Science (Deductive reasoning) Inquiry that asks specific questions – Usually involves the proposing and testing of hypothetical explanations, or hypotheses Hypothesis – Is a tentative answer to a well-framed question, an explanation on trial – Makes predictions that can be tested – Usually expressed as an: If…., then …. statement

21. 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

22. 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 hypothesis Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings

23. A Closer Look at Hypotheses in Scientific Inquiry A scientific hypothesis must have two important qualities – It must be testable – It must be falsifiable An hypothesis can only be proven to be FALSE, never proven to be TRUE!

24. The Myth of the Scientific Method The scientific method – is an idealized process of inquiry There is not “ONE” method May design experiment, then backtrack when realize need more observations May redirect research if realize been “barking up wrong tree” Hind sight is 20/20

25. EXPERIMENTAL DESIGN A CONTROLLED experiment must see the effect of ONE VARIABLE at a time Hard to do in field/lab Don’t eliminate unwanted variables…. cancel their effects by using a CONTROL GROUP Must be repeated (at least 3 X) Can’t ignore or rule out data which do not support the hypothesis

26. VARIABLES A variable is any factor, trait, or condition that can exist in differing amounts or types. – independent variable is the one that is changed by the scientist. – dependent variable is observed to see how it responds to the change made to the independent variable. The new value of the dependent variable is caused by and depends on the value of the independent variable. – controlled variables. are quantities that a scientist wants to remain constant, and must be observed as carefully as the dependent variables.

27. HYPOTHESISIndependent variable (What I change) Dependent variable (What I observe) Controlled variables (What I keep the same) If fertilizer is added, then a plant will grow bigger. Measure amount of fertilizer (grams) Growth of the plant measured by its height Growth of the plant measured by the number of leaves There are other ways to measure growth Same size pot Same type of plant Same type and amount of soil Same amount of water and light Make measurements of growth for each plant at the same time The many variables above can each change how fast a plant grows, so to insure a fair test of the fertilizer, each of them must be kept the same for every pot.

28. “IT’S JUST A THEORY” In every day conversation, a theory often implies an untested guess. In science, the word “theory” means something different than in common usage. Broader than a hypothesis General enough to spin off more hypotheses Supported by a massive body of evidence

29. “IT’S JUST A THEORY” A theory is a well supported, testable explanation of natural phenomena. EX: Cell Theory, Gravitational theory, or Atomic theory http://www.avgoe.de/StarChild/DOCS/STARCH00/questions/apple_falling.gifhttp://sixthsense.osfc.ac.uk/chemistry/atomic_structure2/atom.gif

30. TECHNOLOGY applies scientific knowledge for a specific purpose Copyright © 2005 Pearson Education, Inc. publishing as Benjamin Cummings