FCAT Review The Nature of Science

1) State a problem like asking a question “Which fertilizer works best to grow beans?”

2) Research Use sources such as books, magazines, news papers, journals, and experts to discover background information about your problem.

3) Form a hypothesis a) Use your research and observations to predict an answer to the problem b) Is the purpose for the experiment, let’s other know what you are testing c) should be very specific and based on research

4) Conduct an experiment Procedure – Describes how an experiment will be carried out – step by step This should test only one hypothesis Should only change one variable Decide what equipment and materials are needed Take safety precautions

5) Analyze Data Data – Recorded facts or measurements from an experiment Describe the results in words List the information in a table or graph

Analyzing graphs

6) Draw a conclusion Conclusion – Logical answer to a problem question based on data Think about what the data mean - Are there patterns? Did the experiment test the hypothesis correctly? - Do you need a new experiment? Do the data support the hypothesis? -Was the prediction right or wrong? - Do you need a new hypothesis?

Control – A standard for comparison A specimen or subject kept “normal” while the hypothesis is tested on others a control group has only water – no fertilizer if all groups end up the same, does the fertilizer really do anything? Probably not!

Controlled Variable – Any factor that does not change during an experiment Same for all specimens where the plants are grown, soil, amount of water, etc. Independent – Changed by the experimenter which plants get which fertilizer, X axis the tested variable Dependent – Changes as a result of the independent variable, Y axis bean production for each plant the outcome variable

Importance of Models Benefits and limitations of models Benefits- they can how us things that are too small or too big to be easily seen They show us complex processes They are safer/more stable to use than the real thing Limitations- Not always to scale Not the real thing so there are some factors not considered in models.

Volume – Amount of space occupied by an object Length x Width x Height Cubic meter – SI unit for volume (m3) Measure water displacement in a graduated cylinder

Mass – Amount of matter in an object Kilogram – SI unit for mass Gram, milligram One liter (L) of pure water has mass of 1 kg

Weight – The measure of the force of gravity acting on an object Newton (N) – SI unit for force and weight Weight changes as gravity changes

Density – Amount of mass an object has for its volume Mass/Volume Density =             Mass= Density x Volume Volume= Mass/ Density You need to know how to change around the standard equation!!!! Object Mass Volume Density A 15 3 ? B 4 C 20 D 5 E 21 F 18

Checking Validity WHY IS IT IMPORTANT THAT SCIENTIFIC INVESTIGATIONS ARE REPLICABLE? - So that they other scientists can repeat the experiment to verify the results. WHAT IS THE DIFFERENCE BETWEEN REPLICATION AND REPETITION(Repeated trial)? - Replication is when the whole experiment is repeated by someone else. Repetition(repeated trial) is when you repeat one part or a couple parts to get more accurate results.

Scientific theory vs. Scientific law WHAT IS THE DIFFERENCE? SCIENTIFIC THEORY: A WELL-TESTED EXPLANATION FOR A WIDE RANGE OF EXPERIMENTS AND OBSERVATIONS. (plate tectonics, evolution, cell theory, atom theory) SCIENTIFIC LAW: A STATEMENT THAT DESCRIBES WHAT SCIENTISTS EXPECT TO HAPPEN EVERY TIME UNDER A PARTICULAR SET OF CONDITIONS (gravity, superposition, conservation of mass, conservation of energy)

Science is always changing Science is always changing! New evidence can be discovered to contradict previous theories and ideas *EVIDENCE IS DATA AND OBSERVATIONS THAT HAVE BEEN COLLECTED THROUGH SCIENTIFIC PROCESSES AND THAT ALSO EXPLAIN A PARTICULAR OBSERVATION. *ALL SCIENTIFIC INVESTIGATION INVOLVE THE COLLECTION OF RELEVANT EVIDENCE TO SUPPORT RESEARCHER’S CONCLUSIONS. *SCIENTIFIC EXPLANATIONS ARE BASED ON EVIDENCE, LOGICAL REASONING, PREDICTIONS, AND MODELING.

Sample Question In scientific research, scientists should clearly publish the procedures used in their experiments, along with their observations and data. Whys is it important for someone else to know the procedure? Knowing the procedure allows for replication of the experiment Knowing the procedure helps others understand the reasons for the experiment. Knowing the procedure demonstrates the technical proficiency of the scientist. Knowing the procedure can explain how the data were interpreted by the scientist.

The following statements were taken from the procedures of four different investigations. 1 Pour 50 milliliters (mL) of water down four inclined surfaces. 2 Roll a marble down the ramp from a height of 10 centimeters (cm), 20 cm, and 30 cm. 3 Take the mass of five rocks separately and then determine the average mass in grams (g). 4 Conduct four trials of counting the bubbles produced by a water plant for 1 minute (min) each. The statement from which investigation is an example of repetition(repeated trial)? A. Investigation 1 B. Investigation 2 C. Investigation 3 D. Investigation 4

Sample Question Until the 1500’s doctors thought diseases were caused spontaneously. Scientists began proposing that diseases were caused by seedlike entities that could be passed among people. After the invention of the microscope, doctors came to know that many diseases were actually caused by microscopic living organisms, like bacteria. What does this suggest about the nature of scientific knowledge? A. Scientific knowledge should not be considered valid because it changes over time. B. Technology has improved enough that scientific knowledge can stop changing. C. New discoveries and evidence are more important than repeatable results. D. Scientific knowledge changes over time based on evidence.

Sample Question Scientists create both scientific theories and scientific laws as they make observations and conduct experiments about the natural world. Which of the following statements most accurately compares the difference between scientific theories and scientific laws? A. Scientific laws are based on evidence, while scientific theories are not. B. Scientific theories involve only biology, while laws involve all types of science. C. Scientific theories involve mathematical equations, while scientific laws are based on observations. D. Scientific theories are ideas that explain natural events, while scientific laws more reliably predict natural events.