In your homework stamp sheet (orange), write: 9/12 Reading for Comp. ws *Have your homework out on your desk.

Warmup Open your Bio Notebook to the “Questions” page (page 7) Answer the following questions in complete sentences (on the top half of the page): After reading over the Learning Targets for Unit 1: What do I know about the topics in this unit? What have I heard about these topics? What can I add with help from my partner? What do I want to learn about these topics? What kind of jobs do I think you can get that require mastery of the content of this unit?

Read section 1-2 in your textbook Homework Finish “Let’s Graph” Read section 1-2 in your textbook Write down two main ideas Define vocabulary terms in your own words

Scientific Investigations

Goal of Science Organized way to investigate and understand the natural world To seek the truth in an objective and evidence-based manner Scientia (Latin) - “knowledge” or “to know”

Observation vs. Inference Data we can take in through our senses. Very important to all steps of the scientific method Important that one take good observations and measurements Inference What we can figure out from that data.

Observation Ohh… This liquid is green and it is leaking from a brown can. I also smell it. Observation: when studying something describe only facts that you can see, touch, smell and hear. You are not making any guesses. THIS IS NOT AN OPINION!!

THIS CAN BE A SCIENTIFIC OPINION Inference Based on my observations, I think that this can is old and is leaking a toxic substance. Inference: using your observations to make a guess about an object or an outcome THIS CAN BE A SCIENTIFIC OPINION

Group Practice Give 2 observation on the following: Give 2 inferences on the following:

Scientific Design “Scientific Process” An organized process scientists use which depends on: proposing a TESTABLE hypothesis Designing a CONTROLLED experiment which can be repeated Gathering OBSERVABLE, EMPIRICAL, and MEASURABLE data Composing an evidence-based conclusion after the analysis of that data No ONE way to do the “scientific method” Reduce bias on the part of the scientist Bias- scientist may have a preference of one result over another

9/13/11 Warmup You want to know if a new brand of yeast will make your bread rise more. How do you test this? What do you include in your experiment? **What is DRY MIX?

“Scientific Process” Steps: QUESTION/PROBLEM- based on observations HYPOTHESIS- statement about the relationship between 2 things TESTING- controlled experiment or observations. RESULTS- analyze your qualitative and quantitative data CONCLUSION- confirm/reject your hypothesis; draw up significance of your results Report findings to others so they can repeat the experiment.

Important terms: Important terms: Independent (manipulated) variable (IV): condition or event under study, what you change (manipulate) in the study Dependent (responding) variable (DV): condition that could change under the influence of the independent variable (measure this) Controlled variables (CV): conditions which could affect the outcome of the experiment so they must be held constant (unchanged) among groups.

Variables: Independent vs. Dependent Introduced , “new” condition Intentionally manipulated Controlled Cause AKA: manipulated variable Expected to change in response to IV Intentionally left alone Measured Effect AKA: responding variable Controlled variables: kept the same among all groups, so that they don’t affect the results

Scientific Method Make observation Ask question Develop hypothesis Test hypothesis with an experiment Test hypothesis with further experiments Revise hypothesis Analyze data and draw conclusions Hypothesis: all objects fall when dropped Test this by dropping objects Each object we drop is a test of our prediction, the more successful tests the more confidence in our hypothesis What if we drop a helium balloon? What if we drop something in the space shuttle in space? These are clear exceptions to our original hypothesis-does this make our hypothesis invalid? Hypothesis IS supported Hypothesis is NOT supported Develop theory Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8

Important terms (ctd.) experimental group: group(s) subjected to the independent variable control group: group not subjected to the independent variable, used as measuring stick, represents normal, usual conditions, no independent variable in this group. DIFFERENT FROM CONTROLLED VARIABLES. reproducibility: producing the same result consistently to verify result. Procedures should describe your experimental design in enough detail for others to perform the same experiment in the exact manner.

9/14 In orange HW sheet: 9/14 Sponge Bob WS Warmup

9/13 Warmup: CAN YOU SPOT THE SCIENTIFIC METHOD? A. recognize a problem C. test the hypothesis with an experiment B. form a hypothesis D. draw conclusions _____1. Stephen predicted that seeds would grow faster if an electric current traveled through the soil in which they were planted   _____2. Susan said, “If I fertilize my geranium plants, they will blossom. _____3. Rene grew bacteria from the mouth on special plates in the lab. She placed drops of different mouthwashes on bacteria of each plate. _____4. Dana wanted to know how synthetic fibers were different from natural fibers. _____5. Kathy used a survey to determine how many of her classmates were left-handed and how many were right-handed. _____6. Jonathan’s data showed that household cockroaches moved away from raw cucumber slices. _____7. Michael fed different diets to three groups of guinea pigs. His experiment showed that guinea pigs need vitamin C and protein in their diets. ____8. Bob read about growing plants in water. He wanted to know how plants could grow without soil.

About hypotheses… Must be TESTABLE Relates two variables “If…then…because” IF a variable (IV) is manipulated a certain way, THEN another variable (DV) will respond this way BECAUSE of this reason. Forces you to think about what results in an experiment will look like SUPPORT or REJECTED!!

Choose two and write a plausible hypothesis from these predictions… Chocolate may cause pimples. Salt in soil may affect plant growth. Plant growth may be affected by the color of the light. Bacterial growth may be affected by temperature. Ultra violet light may cause skin cancer. Temperature may cause leaves to change color. Write in “If… then… because…” form

Do students who get more sleep perform better in school? Design an investigation. Question Hypothesis Experiment Identify: Independent variable Dependent variable Variables that must be controlled Experimental group Control group What data will you collect? Qualitative Quantitative (Draw a table)

Theories and Laws What is the difference? HYPOTHESIS: THEORY: Educated guess, based on observations, testable Limited statement regarding cause and effect in a specific situation “My car does not start because the battery is low…” THEORY: Explanation that is accepted as true based on evidence to date. There is enough evidence to accept a group of hypotheses Can be shown to be false if evidence disputes Explains WHY something occurs Theory: a description of the world that covers a relatively large number of phenomena and has met many observational and experimental tests Law of Nature: theory (or group of theories) that has been tested extensively and seems to apply everywhere in the universe-they become part of the conceptual framework of a particular field

Scientific Method Make observation Ask question Develop hypothesis Test hypothesis with an experiment Test hypothesis with further experiments Revise hypothesis Analyze data and draw conclusions Hypothesis: all objects fall when dropped Test this by dropping objects Each object we drop is a test of our prediction, the more successful tests the more confidence in our hypothesis What if we drop a helium balloon? What if we drop something in the space shuttle in space? These are clear exceptions to our original hypothesis-does this make our hypothesis invalid? Hypothesis IS supported Hypothesis is NOT supported Develop theory Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8

Homework tonight Study for your quiz tomorrow Read section 1-3 Sections 1-1, 1-2, 1-3 Read section 1-3