1. Today’s DO NOW DO NOW – You are conducting an experiment to answer the question, “Does water temperature effect the rate at which fish eggs hatch?” Identify what would be the MV, RV and at least 2 controls in this particular experiment.

2. Possible Answers to today’s DO NOW MV – temperature of water RV – time it takes the eggs to hatch Controls – type of fish, age of fish, type of water, same time period given,etc.

3. What is Science? –Way of learning about the natural world. What process of study do scientists use to examine scientific phenomena? –The Scientific Method (Scientific Inquiry) Provides answers and explanations about to problems. Allows scientists to accurately collect data in an organized way.

4. What Skills Do Scientists Use? Observing Inferring Predicting Classifying Making Models

5. Making Observations QUALITATIVE OBSERVATION: –Using one or more of your senses to gather information and collect data. Ex. The worm’s skin is slimy on top Ex. The chemical is blue. QUANTITATIVE OBSERVATION: –Describe using a number or amount Ex. The frog’s intestines measure to 13cm. Ex. The mass of the powder was 5.1 g.

6. Making Inferences Explaining or interpreting the things that you have observed. –Ex. Observation: There is steam coming out of the pot. –Inference: The water is hot, or someone is cooking spaghetti, or the pot has been on the fire for 10 minutes.

7. Making Predictions Making a forecast of what will happen in the future based on past experience of evidence. –Ex. Piscataway football has beat Perth Amboy the last 5 years in a row. It can be predicted that they will win again this year.

8. Scientists Classify The process of grouping together items that are alike in some way. Makes things easier for scientists to compare when observing different groups.

9. Group the following items into categories. What did you base your classifications on?

10. Making Models Involves creating representations of complex objects or processes. Help people study things that are complex or that can’t be observed directly. –Ex. Our microscopes don’t allow us to see DNA, but in class we will put together MODELS of the DNA molecule.

11. Steps Followed By Scientists During the Scientific Method Posing questions based on observations Developing Hypothesis Designing Experiments Making Measurements and Collecting Data Interpreting Data Drawing Conclusions Communicating Results

12. Scientists Pose Questions Scientific inquiry BEGINS with a question or a problem based on an observation. Questions must be able to be tested or investigated, not be personal tastes or judgments –Ex. Does salt affect the time it takes water to boil? –NOT—Does salt make spaghetti taste better? –Ex. Does a low carb diet help you lose weight faster? –NOT –Do pancakes taste better than waffles? –What kind of questions could you pose about television.

13. The Next Step Is To Develop A Hypothesis HYPOTHESIS: –Possible answer to a scientific question –MUST BE TESTABLE. –MUST be written in an If…, then… statement.

14. What belongs in a hypothesis? If statement – shows the relationship between the two variables in the lab. –Ex. IF the amount of salt effects the boiling time of water, –IF the temperature of water correlates with the thickness of the liquid, –IF the temperature of the air is related to the chirping rate of grasshopper,

15. What belongs in a hypothesis? The THEN statement - where you make your most knowledgeable guess as to what you think may happen. –Ex. THEN, increasing the amount of salt will shorten the boiling time of water. –THEN, decreasing the temperature will increase the thickness of the liquid. –THEN, the colder of the air temperature, the more chirps will be counted.

16. Examples of an Hypothesis If sunlight effects the rate of plant growth, then the more exposure to sun the higher the plants will grow. If bacteria grow in higher temperatures, then an increase in temperature will lead to an increase in bacterial growth.

17. Next, You Design an Experiment You need to decide what your VARIABLES are. –Factors that can change in an experiment

18. There are 3 TYPES OF VARIABLES 1. Independent (Manipulated) Variable 2. Dependent (Responding) Variable 3. Controlled Variable

19. Explanation of the INDEPENDENT (MANIPULATED) VARIABLE The variable that is changed during an experiment The variable that the scientists chooses to change The variable that may cause a change in the dependent variable

20. Explanation of the DEPENDENT (RESPONDING) VARIABLE The factor that is being measured in an experiment The variable that is measured by scientists The variable that may change because of the independent variable

21. Explanation of the CONTROLLED VARIABLE (CONSTANT) Variable that stays the same during an experiment Variable that is controlled by the scientist Variable that is not allowed to change

22. What is a placebo? Sometimes, scientists will choose a group of subjects to receive no treatment. They are therefore the control group. A placebo is given to these subjects so that they will not influence any data. The mind can play tricks on the human body, however, if a person receives a placebo they THINK they are receiving the treatment and their mind will not play any tricks on them. Subjects ARE NOT told if they are given the placebo or not. WHY?

23. Scientists Observe To Collect Data Data: –The facts figures and other evidence gathered through observations –If numerical, measured in the metric system

24. Data Tables A way to record results and observations accurately Have a descriptive title Divided into columns & rows Shows the independent variable Provides a place to record the dependent variable Explain how to RECORD DATA

25. Example of a DATA TABLE Number of minutes of exercise per week (min) Total weight loss per week (g) 30 60 90 120 150 Does The Amount of Exercise Effect Total Weight Loss?

26. Make Measurements During Your Experiment Once you have measured the differences in your responding variables. You have to analyze and interpret your data.

27. Graph the data Look for patterns and relations Look at the shape of the graph Next, you draw a conclusion. How do you ANALYZE DATA

28. What do scientists do when they DRAW CONCLUSIONS? Answer the original question State whether or not the hypothesis was supported (it is never “right” or “wrong”) Pose questions for further research

29. Lab Reports Science journals Presentations to other scientists How do scientists COMMUNICATE the results of their work?

30. Why are REPEATED TRIALS necessary in an experiment? To make sure results are valid The more trials conducted, the more likely the results are reliable To make sure a “fluke” is not considered the true result