Biology – The Nature of Science (2012)

1. Biology – The Nature of Science (2012) How do we use science to study life? What tools do we use? How do we share our findings? What characteristics do all living things have?

2. Nature of Science • Definitions / Notes • Inference Activity and Directions • Identifying Variables and Controls • Making Graphs • Experimental Design • Measurement Activity, video worksheet & SI practice • Pseudoscience • Applying Scientific methods

3. Chapter 1 Key terms • Scientific methods • Hypothesis • Experiment • Control • Independent variable (manipulated) • Dependent variable (responding) • Safety symbol • Pseudoscience • Data • Scientific law • Theory • SI units • Biology • Organism • Organization • Reproduction • Species • Growth • Development • Environment • Stimulus • Response • Homeostasis • Energy • Adaptation • Evolution

4. Inference Read the following story and then indicate your response to each of the statements printed below the story. A business man had just turned off the lights in the store when a man appeared and demanded money. The owner opened the cash register. The contents of the cash register were scooped up and the man sped away. A member of the police force was notified promptly. Indicate your response to each of the following statements, by checking "True" if you believe it to be true, "False" if you believe it to be false, and "???" if you cannot determine whether it is true or false. True False ??? _____ A man appeared after the owner had turned off the store lights. _____ A man received cash. _____ The robber was a man. _____ The man who opened the cash register was the owner. _____ The store owner scooped up the contents of the cash register. _____ Someone opened a cash register. _____ The cash register was empty when the owner opened it. _____ After the man scooped up the contents of the cash register, he ran away.

5. Directions • To unlock the secrets of Science, ALL that is needed is curiosity, a well-ordered or logical mind, patience, ABILITY TO FOLLOW DIRECTIONS, a respect for safety while dealing with equipment and chemicals, and (last, but not least) a knowledge of elementary mathematics. • FOLLOWING DIRECTIONS EXERCISE • The answer to each question is yes. If you cannot answer yes, go back and redo the previous step or steps. • Obtain a square sheet of paper. • Fold the paper diagonally. • Position the triangle on the desk with the long side facing you. • From left t o right, 1abe1 the corners A, B, C. • Fold point C along edge AB, so that the top edge of the fold is parallel to the base of the original triangle. Do you see three triangles? • From left to right, label the corners of the triangle you just made D, E, F. • Fold A to point F. Do you see four triangles? If not, Go back two steps. • Fold a single layer of side B down in front as far as it will go. • Turn facedown the side with E showing. • Fold the flap, which is now showing, as far down as it w ill go. • Fill the CUP with water. Is it watertight? If it leaks, get a new piece of paper and go back to step 1.

6. Scientific Method Designing an Experiment Scientific Method and the Holy Grail State the Problem Analyze Results Form a Hypothesis Draw a Conclusion Set Up a Controlled Experiment Publish Results Record Results Scientific Method Activity

7. Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks. • Control Group • Independent Variable (manipulated variable) • Dependent Variable (responding variable) • What should Smithers' conclusion be? • How could this experiment be improved?

8. Homer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of "treatment" there is no change in the appearance of the green slime on either side of the shower. • What was the initial observation? • Identify the Control Group • Independent Variable • Dependent Variable • What should Homer's conclusion be?

9. Krusty was told that a certain itching powder was the newest best thing on the market, it even claims to cause 50% longer lasting itches. Interested in this product, he buys the itching powder and compares it to his usual product. One test subject (A) is sprinkled with the original itching powder, and another test subject (B) was sprinkled with the Experimental itching powder. Subject A reported having itches for 30 minutes. Subject B reported to have itches for 45 minutes. Identify the-16. Control Group 17. Independent Variable 18. Dependent Variable 19. Explain whether the data supports the advertisements claims about its product.

10. Bart believes that mice exposed to microwaves will become extra strong (maybe he's been reading too much Radioactive Man). He decides to perform this experiment by placing 10 mice in a microwave for 10 seconds. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. he found that 8 out of 10 of the microwaved mice were able to push the block away. 7 out of 10 of the non-microwaved mice were able to do the same. Identify the-11. Control Group 12. Independent Variable 13. Dependent Variable 14. What should Bart's conclusion be? 15. How could Bart's experiment be improved?

11. Lisa is working on a science project. Her task is to answer the question: "Does Rogooti (which is a commercial hair product) affect the speed of hair growth". Her family is willing to volunteer for the experiment. 20. Describe how Lisa would perform this experiment. Identify the control group, and the independent and dependent variables in your description.

12. Analyzing and Presenting Data All graphs should include the following: Title Units Labels Even spacing The Line Graph -This kind of graph shows the relationship between two kinds of data in which the independent variable is continuous. The Bar Graph-Bar graphs are used when there is no continuity from one piece of data to the next. Y Axis – Dependent Responding Variable X Axis – Independent Manipulated Variable Making graphs

13. Candle Activity: Identify phenomena Develop a testable hypothesis Design an experiment to test your hypothesis

14. Measurement • Most scientific studies and experiments use a standard system of metric units called Le Système International d’Unités, or SI for short. • SI is a modern version of the metric system based on a decimal system that uses the number 10 as the base unit. • Length • The standard SI unit to measure length is the meter (m). • The meter is divided into 100 equal parts called centimeters (cm). • The centimeter is divided into 10 equal parts called millimeters (mm). • Long distances are measured in kilometers (km) which is 1,000 m. Weight and Mass Weight is a measure of the gravitational force on an object. • Weight varies with location depending on gravitational force. • Weight is a force, and the SI unit for force is the newton (N). • Mass is the amount of matter in an object. • The mass of an object, unlike weight, does not change with an object’s position. Introduction to Measurement worksheet

15. Methods of Scientists Measurement Area and Volume • Area is the amount of surface included within a set of boundaries and is expressed in square units of length, such as square meters (m2). • The amount of space occupied by an object is the object’s volume. • The SI units for volume are derived from the SI units used to measure length. • The basic SI unit of volume for a regularly shaped, solid object is the cubic meter (m3). • SI measurements for liquid volumes are usually made in milliliters (mL) or liters (L). Measurement Activity

16. Methods of Scientists Measurement Time • Density is a measure of the amount of matter that occupies a given space. • Density is calculated by dividing the mass of the matter by its volume. • Time is the interval between two events and is usually measured with a watch or clock. • The SI unit of time is the second (s). Density Temperature • Temperature is a measure of the average vibrations of the particles that make up a material. • A mass made up of particles that vibrate quickly has a higher temperature than a mass whose particles vibrate more slowly. • Temperature is measured in degrees with a thermometer. • In science, temperature is often measured on the Celsius (C) scale. • In SI, temperature is measured on the Kelvin (K) scale.

17. Scientific Notation • To express numbers that are very large or small, scientists use a type of shorthand called scientific notation to express the number as a multiplier and a power of 10. • In scientific notation, a number is expressed as a value between 1 and 10 multiplied by a power of 10. • The power of 10 is the number of places the decimal point must be shifted so that only a single digit remains either to the left or right of the decimal point. • If the decimal point must be shifted to the left, the exponent of 10 is positive. • If the decimal point in a number must be shifted to the right, then the exponent of 10 is negative. For example: 90 000 000 000 = 9 X 1010 5 974 200 000 000 000 000 000 000 = 5.9742 X 1024 0.0000000001 = 1 X 10-10 SI Practice Problems

18. Objectives Essential Questions • List several ways in which scientific information is communicated. • Differentiate between a scientific theory and a scientific law. Vocabulary • theory • law Communicating Results • One important goal of science is to make results available to others. • Communicating scientific data and results allows others to learn of new discoveries, to possibly verify what has been reported, and to conduct new experiments using the information.

19. Communicating Results Lab Reports • Throughout this course, you will conduct many science experiments and activities. • During and after each activity or experiment, you will be asked to record and analyze the information that you collected and to draw conclusions based on your data. • Your resulting lab report, similar to the one on the right, will be used to assess your understanding of the activity or experiment.

20. Communicating Results • A line graph is a visual display that shows how two variables are related. Graphs y axis • The independent variable is plotted on the horizontal (x)axis. • The dependent variable is plotted on the vertical (y) axis. x axis

21. Theories and Laws • A scientific theory is an explanation based on many observations during repeated experiments. • A scientific theory is valid only if it is consistent with observations, makes predictions that can be tested, and is the simplest explanation of observations. • A theory can be changed or modified with the discovery of new data. • A scientific law is a basic fact that describes the behavior of a natural phenomenon. A scientific law can be thought of as a “rule of nature,” even though the cause of the law may not be known. The events described by a law are observed to be the same every time. Theories are often used to explain scientific laws.

22. Science vs. Pseudoscience Science: “Extraordinary claims require extraordinary proof” Make a list of differences between science and pseudoscience Eyes of Nye Applying Scientific Methods

23. Biology Characteristics of living things Characteristic Examples Living things are made up of units called cells. Many microorganisms consist of only a single cell. Animals and trees are multicellular. Living things reproduce. Maple trees reproduce sexually. A hydra can reproduce asexually by budding. Living things are based on a universal genetic code. Flies produce flies. Dogs produce dogs. Seeds from maple trees produce maple trees. Living things grow and develop. Flies begin life as eggs, then become maggots, and then become adult flies. Living things obtain and use materials and energy. Plants obtain their energy from sunlight. Animals obtain their energy from the food they eat. Leaves and stems of plants grow toward light. Living things respond to their environment. Despite changes in the temperature of the environment, a robin maintains a constant body temperature. Living things maintain a stable internal environment. Taken as a group, living things change over time. Plants that live in the desert survive because they have become adapted to the conditions of the desert. Its Alive 1 Its Alive 2

24. What are the Characteristics of Life? Biotic – living components of an ecosystem Abiotic – Nonliving component of an ecosystem Known species1,412,000 • All things living have the following specific properties: • Cellular organization • Metabolism • Homeostasis • Reproduction • Heredity Other animals281,000 Fungi69,000 Insects751,000 Prokaryotes4,800 About 1.4 million species have been identified, but estimates of number of species range from 3.6 million to 100 million Plants248,400 Protists57,700