Biology is a Discipline of Science

1. Biology is a Discipline of Science Using the scientific method, biologists have discovered patterns in the living world that explain both its unity and diversity.

2. Unit 1: Key learning • The unity and diversity of life indicate that all living things evolved from a common ancestor. • The scientific method is a systematic approach to problem solving that increases the speed at which discoveries are made AND allows scientists to have confidence in the theories that are generated.

3. Unit 1: Essential questions 1. What common characteristics unite Earth’s diverse forms of life? 2. How is the scientific method used to establish biological theories?

4. Launch activity: Working collaboratively (???) with your partner, write a list of at least 2 reasons why each object should be considered a living organism and 1 reason why it shouldn’t.

5. Launch summary: • List only characteristics you felt are shared by every living thing on Earth. • What are the major kingdoms that demonstrate these characteristics.

6. Unit 1: Concepts • The unity and diversity of life (I) • The scientific method (E) • Scientific theories(E)

7. Essential questions 1.1 & 1.2: • What characteristics are shared by all living things? (Unity) • 2. Why do all living things share these characteristics, but differ in other ways? (Diversity)

8. Question: What are some of the major groups (kingdoms) that living things are divided into? Protista Animalia Bacteria Plantae Archaea Fungi

9. Kingdoms continued • All organisms that are placed into a kingdom share common characteristics with all other members of that kingdom. • Organisms from different kingdoms generally differ greatly from one another.

10. Despite being diverse in appearance, Earth’s organisms share 6 common characteristics. • All forms of life (simple or complex) need to satisfy a few basic needs in order to survive. • The better an organism is at satisfying these needs, the more likely it is to survive and reproduce.

11. Six characteristics unify the diversity of living things. • Cellular organization • Metabolism • Homeostasis • Growth and development • Response to stimuli • Heredity

12. Cellular organization(the cell theory) • All organisms are composed of one or more cells. • All cells arise from pre-existing cells. • Cells are the smallest unit of structure and function; in other words, the smallest structure considered to be alive. • Cell structures have forms that help them to do their jobs. • The activities of cells are controlled by information stored in their genes.

13. Question: Does form determine function, or does function dictate form? This concept will be continually explored over the course of this unit and again as we deal with these topics in depth in later units. Generally speaking…If you change the form of something you change its functionality or its ability to function within the body.

14. Question:What are 3 living organisms that you would call biological producers?What are 3 living organisms that you would call biological consumers?

15. 2. Metabolism • Sequential chemical reactions are necessary for organisms to obtain or use energy. • Energy is necessary to sustain life. • All energy enters the biosphere when producers use photosynthesis or chemosynthesis to store energy. • Some organisms called consumerscan only obtain energy by ingesting other organisms.

16. 3. Homeostasis • Homeostasis is the maintenance of a steady internal environment in response to a changing external environment. • All living things must maintain a stable and consistent internal environment in order to effectively conduct their metabolism.

17. Question: What types of things does your body do to maintain homeostasis? • Pressure sensations cause you to release solid and liquid wastes. • Hunger sensations cause you to eat. • Dry mouth sensations cause you to drink. Individual cells must also regulate their internal environments in response to chemical cues and imbalances.

18. 4. Growth and development • All organisms begin life as a single cell. • Multicellular organisms increase their size through a growth process driven by cell division. • As cells divide, they may take on specialized functions during the process of development(zygote-embryo-infant-adolescent-adult).

19. Question: How is fetal development different than development once a human is born? • Fetal development is a much more drastic metamorphosis, with tissues (muscle, nervous, etc.) being formed from undifferentiated cells, while development after birth is more cognitive (our ability to understand our world). • In order for cells to correctly differentiate and take on their proper functions, development must not be affected by chemical mutagens such as drugs, alcohol or caffeine.

20. Question: Why does your body feel pain? • The perception of pain helps your body to avoid those things that might cause bodily harm. • We can also assume that fear is necessary to help us avoid potential pain that may result from our actions. • Ironically, organisms in a natural setting that are most likely to act against their fears, have the most to lose and the most to gain!

21. 5. Responsiveness to stimuli • Organisms must respond to the world around them, in order to: • find food, • locate shelter, • find mates, • Escape from danger. • Cells may not have the complex sensory abilities of multicellular organisms, but they must still perceive the environment around them in order to maintain homeostasis (open and close gates, communicate with other cells).

22. 6. Heredity • Reproduction keeps a species alive, since no individual lives forever. • Information is passed from one generation to the next (heredity) and defines the characteristics of that generation. This passage of information from generation to generation is the reason why evolution occurs.

23. Going Further: Heredity and evolution • Genes store information regarding the structure of specific proteins. • Genetic information is stored in a molecule called DNA. • Changes in the DNA of a gene are called mutations, and lead to variations in organisms (blue or brown eyes). • The differing success of these variations is called natural selection. • Natural selection occurs when organisms with favorable characteristics survive and reproduce- this is just one mechanism for evolution.

24. Question: Suppose you find an object that looks like an organism. How might you determine if your discovery is indeed alive? You would look for evidence of… • Cellular structure and function • Metabolism • Heredity • Growth and development • Homeostasis • Responsiveness to stimuli

25. Unit 1: Concepts • The unity and diversity of life (I) • The scientific method (E) • Scientific theories(E)

26. Unit 1: Concepts • The unity and diversity of life (I) • The scientific method (E) • Scientific theories(E)

27. Essential question 2.1: What steps must be taken to ensure a proper application of the scientific method?

28. Scientific method basics…

29. The Scientific method is a systematic approach to problem solving. Steps required in using the Scientific Method • Generate questions • Conduct background research • Develop a hypothesis and make predictions • Devise an experiment to test the prediction • Conduct the experiment and analyze data • Draw conclusions based on observed data • Repeat the tests or devise new ones • Submit results and conclusions for publication

30. 1. Generate questions about objects, organisms and/or events that can be answered through scientific investigations (i.e. natural as opposed to supernatural phenomenon). • Questions that do not deal with the physical world are un-testable. • Questions may arise in many ways: • Human curiosity, such as “How did the universe form?” • Human need, such as “How can we prevent cancer from killing a patient?” • Questions may arise during a different scientific investigation and be reported in scientific papers as avenues for future study. • The question will appear in the “Introduction” section of a scientific paper.

31. Question: What are some problems that science might seek to solve? • How does a new drug affect the growth of cancer? • How has a population fluctuated as a result of environmental distress? • Science can not address questions that are supernatural such as “Did God create the Earth?”

32. 2. Conduct background research in order to understand the context of the problem (e.g. literature search, continued observation, limited experimentation, etc.). • Scientific journals provide peer reviewed resources documenting the conclusions of past investigations. • Continued observations may yield a deeper understanding of the question / problem. • A pilot study may be undertaken to provide for a deeper understanding of a problem. • The “Introduction” section of a scientific paper will include any research necessary to provide a context (understanding) for the question / problem.

33. 3. Develop a hypothesis (educated guess) and use it to make predictions that follow the “if-then” process. • Hypotheses are “educated” guesses since they are based upon background research. • A hypothesis such as “I believe that the more active a body is, the greater the breathing rate will be,” allows a researcher to develop a prediction such as, “If I put a man on treadmill, then his breathing rate should rise above its resting level.” • The hypothesis will appear in the “Introduction” section of a scientific paper.

34. 4. Devise a way to test the prediction (i.e. making systematic observations, constructing theoretical models, conducting experiments). • Experiments should be well controlled and represent the smallest departure from the natural state of a system. • One variable (the independent variable) should be tested at a time, in anticipation of a change in the dependent variable. • By testing one variable at a time, a scientist can determine whether altering that variable produced the desired result. • The experimental design will appear in the “Methods” section of a scientific paper.

35. 5. Conduct the test and analyze experimental data using a variety of statistical methods. • Data should be collected in tables and analyzed using graphs and other statistical analysis techniques designed to determine the reliability of trends. • Trends observed in large data sets are more reliable than those seen in smaller sets. • The analysis techniques that were employed will appear in the “Methods” section of a scientific paper while the tables and figures will appear in the “Results” section.

36. 6. Draw conclusions based on observed data; in other words, did the experiment support or refute the hypothesis. • Many investigations will not support the hypothesis but do offer a researcher the ability to eliminate a possibility. • Very often the experimental design is flawed in such a way as to cause a researcher to redesign the experiment.

37. 7. Repeat the tests or devise new ones that address experimental error or faulty design • If the test was not flawed and did support the hypothesis, repetition should be completed; time, money and availability of subjects / specimens will determine how much repetition is acceptable. • If a test was flawed, the researcher will need to redesign the experiment to address the errors and again assess the ability of the investigation to answer the question at hand.

38. 8. Submit results and conclusions for publication with suggestions made for additional steps that might be done experimentally. • Once conclusions are made, a researcher must submit their work to a peer reviewed journal to be evaluated prior to publication. • Published journals will provide other researchers in the field access to the conclusions made and allow them to advance their own research. • Researchers will often make hypothesis during the presentation of their conclusions and suggest additional steps that might be taken to continue their work. • The data used to make conclusions will appear in a the “Results” section of a scientific paper while the conclusions and other related details will appear in the “Discussion” section of a scientific paper.

39. Scientists use common speech and measurements to make their results understandable to people all around the world. • Scientific terminology is written in latinin order to keep it consistent within each language. • Felisconcolor rather than Mountain Lion • Measurements are made using metric units so that scientists are all using a common system. • 1 kilogram rather than 2.2 pounds • The results of scientific experimentation are reported using a refereed system of scientific papers. • Each paper reports specific information in a standard fashion.

40. IV. The variable to be tested is compared to a control group. • Only one idea at a time should be tested (variable). • The controlgroup receives no experimental treatment and closely approximates reality. • The results of the variable can be compared to the control to see if a change occurred.

41. V. There are actually two variables in each experiment. • The manipulated variable is the one factor that is changed. • A variable group exercises 3 days a week, while a control group maintains their normal routine. • The responding variableis what you expect to change in response to your “tinkering”. • The variable group loses weight, while the control group maintains their normal weight.

42. Question: How can we measure the affect of exercise on the rate of breathing? • Generate question- completed! • Conduct background research • Develop a hypothesis and make predictions • Devise a way to test the prediction • Conduct the test and analyze experimental data • Draw conclusions based on observed data • Repeat the tests or devise new ones • Submit results and conclusions for publication

43. Question: What was the independent (manipulated) variable in our experiment? The amount of activity was the manipulated variable since it’s what we altered. The rate of breathing was the responding variable (dependent) since it’s what we measured to see if there was a change. The rate of breathing “responded to” the amount of activity.

44. VI. Scientific writing is presented using a standardized journal format that allows readers to find evidence of each of the part of the scientific method • The MASD science faculty have compiled a manual to aid you in the process of writing scientific papers- keep if for the entire year! • In Biology class, we will write each of the sections of a scientific paper after an appropriate lab activity. • In addition to the specifics of scientific paper formatting, we expect you to write with attention paid to proper grammar and spelling.

45. Bubble-ology Lab • Read the introduction and complete the Pre-lab portion of the bubble-ology lab packet.

46. Unit 1: Concepts • The unity and diversity of life (I) • The scientific method (E) • Scientific theories(E)

47. Essential question 3.1: How does an idea become a scientific theory?

48. Stop and Read • Handout the article – “Problems with Vocabulary, Science and Culture” • Pick one group member to report out to the class during discussion.

49. ARTICLE SUMMARY STATEMENT The author uses the evolutionary theory to exemplify the difference between the technical and everyday use of the term “theory.” This is similar to the misuse of the terms idiot (adult with a mental age of 3 or less) and moron (mental age of 8-12).

50. VI. Hypothesis, theories, and laws represent differing degrees of certainty within the scientific world. • A hypothesis is an educated guess, and must be tested scientifically before it is confirmed or rejected. • A theory is our best explanation for a large number of observations. • In order to survive, it must stand the test of time, and repeatedly produce accurate hypothesis. • In order to be scientific, a theory must be falsifiable. • A lawis a directly observable explanation for how the physical universe will behave under certain conditions. • Generally explained by an equation.