Copyright Pearson Prentice Hall Thinking Like a Scientist: Overview of the Scientific Method Is a process for experimentation that is used to explore observations and answer questions. Scientist use the scientific method to search for cause and effect relationships in nature and, to solve problems. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Make an observation Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Steps of the scientific method: Make an observation: the act of studying objects or events using your senses. There are two types of observations that can be collected during an experiment: -Qualitative observations -Quantitative observations Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Qualitative observations: Root word? Quality Qualitative observations are: -descriptive -involve characteristics that can’t easily be measured. -Obtained by using your senses. -Example: color, texture, smell Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Quantitative observations: Root word? Quantity Quantitative observations are: expressed with numbers obtained by counting or measuring. Example: mass, volume, temperature, length Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 2. Observations lead to questions Copyright Pearson Prentice Hall

Explaining and Interpreting Evidence 3. Scientist formulates hypotheses to answer these question. A hypothesis is a proposed explanation for a set of observations. It must be testable. -know an “Educated Guess” Why? -educated because it is based on prior knowledge or you did some background research on the fish. -a guess because it can be proven true or false. Copyright Pearson Prentice Hall

Explaining and Interpreting Evidence Best method of forming a hypothesis: -it must be a statement -it can not be a question -BEST to use a If…………then……….. statement Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 4: Scientist then set up and perform controlled experiments An experiment is the planned steps used to test whether your hypothesis. -Test only one factor at a time -uses 1 control group and one or more experimental groups. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall The control group gets NO experimental treatment. -it is the setup as close to normal conditions as possible/serves as a standard of comparison. The experimental group(s) is the same as the control group except one factor, the experimental variable, is altered in each experimental group. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 5: Scientist collect data during the experiment. Both qualitative and quantitative observations can be made but qualitative observations hold more weight in an experiment -Qualitative observations use the SI units of the International System of Measurement or metric system. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall All qualitative observations use the “International System of Measurement” or SI units: Examples of SI measurements we will collect in this classroom: Measurement SI label Tool Length   Mass Temperature Liquid volume Solid volume meter metric ruler balance grams Degrees Celsius thermometer liter graduated cylinder cm3 (LxWxH) Metric ruler Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 6. Scientist then analyze the data collect. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7. Form a conclusion based on the data collected. 8. Hypothesis is not supported….go back to step 2. (and form a new hypothesis and setup a new experiment ) If the hypothesis was supported by the data ……then the scientist must…… Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall replicate their work and truthfully share their work and results by publishing/Report their results. Copyright Pearson Prentice Hall

EXAMPLE of a Controlled Experiment Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall We came into the classroom and noticed that our healthy and young pet goldfish had died over night!!! We also noticed a that the aquarium heater was malfunctioning. Our hypothesis: If the water in the tank was too hot then the fish would have died. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Our controlled experiment will have four set ups Control group (as close to normal conditions as possible for a goldfish) and three Experimental groups (each identical to the control setup except for the one variable that is being tested). Our experimental variable will be temperature. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Our Control setup: As close to normal conditions as possible; room temp (22 degrees Celsius) , 1 of the same type of plants 3 gallons purified water , 50 grams of stones 3 fish (same age and type), .5 grams of food each day, 14 hours of light , pH of 7 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Our three Experimental Setups: tank 1 tank 2 tank 3 12 degrees 32 degrees 42 degrees In each tank: 3 gal purified water , 50 grams of stones 3 fish (same age and type), .5 grams of food each day, 14 hours of light , pH of 7 and 1 of the same type of plants Copyright Pearson Prentice Hall

If all the fish in experimental tank two and three died, what conclusion might you draw? Our control group: Our three Experimental Setups: tank 1 tank 2 tank 3 22 degrees 12 degrees 32 degrees 42 degrees In each tank: 3 gal purified water , 50 grams of stones 3 fish (same age and type), .5 grams of food each day, 14 hours of light , pH of 7,2 of the same type of plants Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Data collected from our goldfish experiment: Analyze the data Form a conclusion 12 degrees 22 degrees 32 degrees 42 degrees Fish 1 Slow moving Slow respiration rate 10 breaths/min Faster moving Faster respiration rate 32 breaths/min Died after 30 min Died after 1 min Fish 2 12 breaths /min 40 breaths/min Died after 45 min Died after 3 min Fish 3 15 breathes / min 35 breaths /min Died after 22 min Died after 2 min. Copyright Pearson Prentice Hall

Example of an UNCONTROLLED Experiment Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall We came into the classroom and noticed that our healthy and young pet goldfish had died over night!!! We also noticed a that the aquarium heater was malfunctioning. Our hypothesis: If the water in the tank was too hot then the fish would have died. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Our Control setup: As close to normal conditions as possible; room temp (22 degrees Celsius) , 1 of the same type of plants 3 gallons purified water , 50 grams of stones 3 fish (same age and type), .5 grams of food each day, 14 hours of light , pH of 7 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Our three Experimental Setups: tank 1 42 degrees 3 gal purified water , 50 grams of stones 3 fish (same age and type), .5 grams of food each day, 14 hours of light , pH of 7 and 1 of the same type of plants tank 2 42 degrees 20 gal purified water , 200 grams of stones 2 fish (different types), .5 grams of food each day, 14 hours of light , pH of 7 and 3 of the same type of plants tank 3 32 degrees 50 gal purified water , 500 grams of stones 10fish (different types), 10 grams of food each day, 14 hours of light , pH of 7 and 6 of the same type of plants Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Homer Simpson 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 out by spraying half of the shower with 10 ml of coconut juice. -He sprays the other half of the shower with 10 ml of water. -After 3 days of "treatment" there is no change in the appearance of the green slime on either side of the shower. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Your boss thinks that a special juice will increase the rate in which his employees work. -He creates two groups of 50 workers. -Each group is given the same task to perform. -The task given to the workers is to staple a sets of papers. -Group A is given the 50 ml of a special juice to drink while they work. -Group B is not given the special juice, they are given 50 ml of water to drink.. -After an hour, your boss counts how many stacks of papers each group has made. -Group A made 1,587 stacks -Group B made 2,113 stacks Copyright Pearson Prentice Hall