UNIT 1 – Science of Biology NOTES Fill in packet during discussion. Be ready to make concept and vocabulary list.

1. UNIT 1 – Science of Biology • NOTES • Fill in packet during discussion. • Be ready to make concept and vocabulary list.

2. Topic 1A: Characteristics of Living Things

3. BIOLOGY– The study of life Living things are known as organisms. The living world and the non-living world are mixed. As you look out the window here at school or as you investigate any environment you will find a mixture of the two. How can we identify something as an organism? For each of the items listed below state a reason that makes it living or non-living: Clouds Mushrooms Fire Automobile Worm

4. What characteristics do all living things share? 1. Living things are made up of units called cells • Some organisms are made of only one cell and some are made of trillions of cells. • Cells are small self-contained units of living material that are separated from the surroundings by a barrier.

5. Unicellular– organism made of only one cell Multicellular – organism made of more than one cell. In complex multicellular organisms such as humans, many different types of cells work together to perform the functions needed by the organism.

6. Living things reproduce: • Reproduction is the life process that provides for continuation of the species. An individual will not die if it does not reproduce but the species will end if no members reproduce.

7. Terms to know: Sexual reproduction- requires cells from 2 parents to create a new individual different from each parent. Common in multicellular organisms (trees, birds etc.) Asexual reproduction – requires only one parent. Offspring is identical to parent.

8. The traits of living things are determined by the genetic code: • When organisms reproduce they pass on genetic information in the form of DNA to the offspring. • In sexually reproducing organisms the offspring obtain a mixture of genetic information from each parent. • In asexually reproducing organism the offspring have identical genetic information to the parent

9. Living things grow and develop. • Every organism has its own life-cycle – a pattern of growth and change that occurs over the organisms lifetime.

10. Living things obtain and use materials and energy. • Examples • Oxygen and sugar are needed by organisms to make energy. • Food is needed to help build the body

11. Chemical reactions take place in the body to convert the materials from the environment into forms usable by the organism. • Metabolism is the collection of all the reaction that take place within an organism. • Examples of Metabolic Reactions: • Building Cells • Breaking down cells • Converting oxygen and glucose to energy and carbon dioxide.

12. 6. Living things respond to their environment. Organisms live in a constantly changing environment. Examples: Light, temperature and amount of water change from day to day and season to season. Plants and animals must respond to these changes or they will die.

13. 7. Living things maintain and a stable internal environment. The steady state (balance) inside an organisms body is known as HOMEOSTASIS. While the environment outside changes an organism must be able to keep conditions inside mostly the constant. If homeostasis is disturbed the organism will become sick and will die if the balance is not fixed.

14. 8. Taken as a group, living things change over time Life has changed significantly over the history of the earth. The process of this change is known as evolution.

16. CHECK YOUR UNDERSTANDING #1: (Complete in Chapter Summary Packet) In essay format discuss what characteristics all living things have in common and how life on earth is different. Be sure to include the following terms in your response in a way that demonstrates an understanding of the term: Organism, unicellular, multi-cellular, sexual reproduction, asexual reproduction, life cycle, metabolism, homeostasis, evolution

17. Sample Essay Living things (organisms) can be distinguished from non living things by several characteristics and abilities. All organisms are comprised of cells. Whether organisms are made up of a single cell (unicellular) or many cells (multicellular) they are able to carry out similar processes. To continue the species all organisms must be able to reproduce. Some species reproduce by combining genes from two parents in a process known as sexual reproduction. Some species reproduce asexually and produce a genetically identical offspring. All organisms carry on chemical reactions in their body, called metabolism, that allow them to maintain a state of homeostasis or internal balance. Over time, life on earth has evolved to include these common characteristics, but life has developed many different ways of accomplishing these processes.

18. Topic 1B: The Scientific Process What is Science? Science comes from a Latin word which means “to know” Therefore, Science is a way of knowing…. It is what we use to answer a question about the natural world

19. Science is all about inquiry. People ask questions about nature and what they observe and then actively seek to find answers. The process of finding answers is known as the Scientific Method.

20. The scientific method has brought us the technology we enjoy today. These inventions are not the result of any one discovery but the total knowledge collected over centuries of scientific inquiry.

21. The steps of the Scientific Method? 1-Define the problem (What’s the Question) What are you trying to find out? What just happened? Why does it do that? HUH?

22. Write 2 questions about the natural world which you have wondered about? Examples of questions: Why do pigeons bob their heads when they walk? Why do leaves turn color in the fall?

23. 2-Formulate a Hypothesis Hypothesis- A possible explanation for an observation that can be tested. Example: Pigeons bob their heads because it helps them see better.

24. 3-Testing the Hypothesis- Experimentation Finding a procedure to either verify or disprove the hypothesis Hypothesis is accepted only when predicted effects are observed and repeatable

25. A. Experiment design is critical to make experiment and hypothesis accepted • Controlled Experiment- Situation is set up more than once to test your hypothesis • Variable- A single factor in the experiment is changed to see if this has an effect on the results • Control group- One group in the experiment where no change is made.

26. Characteristics of a well designed experiment: • The sample size is large enough to draw a valid conclusion about the hypothesis • Only one significant variable is tested through the experiment. • A control group is present • Conclusions must be based on measurable quantities or clear criteria and not subject to opinion of the observer.

27. The dependent variable is the one that changes is response to the other variable. The independent variable is the one that causes the change the other variable.

28. In investigating questions where one factor (variable) is dependent on another, phrase the tests as: The effect of ___________________ on ___________________________. Or ______________________________ depends on _____________________

29. Example The effect of rain amount on oak tree growth. The growth of the tree depends on the amount of rain. Therefore we call the growth of the tree the dependent variable and the amount of rain the independent variable.

30. In the relationships below circle the dependent variable and underline the independent variable. (look for things that can be measured) 1. People gain weight based on the amount of calories they take in. 2. The amount of sunlight available influences how fast a tomato will ripen. 3. The amount of television watched by children impacts attention span

31. In general the dependent variable is plotted on the y-axis and the independent variable is plotted on the x-axis. Example: Hypothesis – The more time a student spends thinking before blurting out, the less time they spend in the Assistant Principals office. Fill in the dependent and independent variables on the axes below: Time in AP office Time spent thinking before speaking

32. B. Measuring Variables i. International System Units Meter Ruler Gram Balance/Scale Liter Graduated Cylinder Seconds Stop Watches Celsius or Kelvin Thermometer

33. ii. The Scale of Biology

34. For each of the following organisms listed below choose the appropriate scale of measurement (metric) for scientists to use: • Weight of an Elephant __________________ • Width of a Bacteria _____________________ • Temperature of a liquid ________________ • Length of a feather ___________________ • Weight of a feather ___________________ • Height of a person ____________________ Kilograms Micrometers Celsius or Kelvin Centimeters Grams Meters

35. 4-Analyzing and Drawing Conclusions • Looking at data obtained in the experiment- • (Use graphs, charts, pie graphs etc.) • II. Looking for patterns or relationships • Draw a conclusion about your data • (Does the data support your hypothesis or not)

36. 5-Reporting Observations- Record your data and report in detail your means experimentation and observed results Scientists must report all the details because the experiment has to be repeatable.

37. Practice Graph Problems A. Baby chicks require a constant source of food. As chicks grow, more energy is required for daily activities. The following table gives the grams of food eaten by a chick over a five day period. Graph in packet

38. A water plant placed in bright light gives off bubbles of oxygen. In the lab, it was noticed that if the light were placed at different distances from the plant in the aquarium, the rate of bubbling varied. Plot a graph of the following data.

39. 6. Tying Discoveries Together A. Theories and Laws Theory-Explanations that apply to a broad range of phenomena and that are supported by experimental evidence Scientific Law- Statement that describes some aspect of a phenomenon that is always true

40. How do you tell the difference between a Scientific Theory and Scientific Law? • A Scientific Law relates to a single action • Example: Gravity • A Theory explains a series of related phenomena • Example: Evolution • Cell Theory

41. Both theories and laws are well tested and widely accepted. • Parts of theories can be adapted to new discoveries or to make them more understood, but the overall theory will not change. • Laws are not flexible but can be put into simpler words.

42. Laws and Theories are different then Hypotheses. • Laws and theories are well tested by experimentation. • Hypotheses are educated guesses based on an observation before they are tested.

43. Remember: All Hypotheses are Valuable: Even if a hypothesis (testable guess) is false it is a valuable tool because it may lead to further investigations.

44. Topic 1C: Laboratory Techniques A. Main Techniques used in Biology 1.Centrifugation Materials of different densities suspended in a liquid can be separated by spinning a tube at high speeds 2. Micro dissection Tiny instruments that work on one cell at a time

45. 3. Tissue Culture Maintaining living cells of tissues outside the body (in vitro) 4. Chromatography A technique that separates different substances from each other on the basis of chemical or physical properties  5. Electrophoresis A technique that separates proteins, nucleic acids(DNA), and other substances with an electric current

46. 6. Spectrophotometry Using light to analyze what a substance is and how much is present. “Photo” means - Light • Staining – • A technique in which a dye is added to make a substance within a cell easier to observe.

47. 8. Microscopy The microscope is perhaps the most important tool in the history of biology. The invention of the microscope opened up the worlds of cells to scientists. The two types of microscopes used in this class are compound microscopesanddissecting microscopes.

48. Important Microscope Vocabulary Magnification – enlargement of an object 100X means that the image appears 100 times bigger than the actual object. Resolution – the ability of a microscope to show detail (clarity, sharpness).

49. Compound light microscope: The compound light microscope brings light to your eye through a combination of lenses that allow you to see small “Micro” sized objects in a magnified form.

50. To determine magnification you multiply the power of each lens used. 4 (objective) X 10 (eyepiece) = 40 magnification