Science Process Skills Three Types of Investigations Scientific Method Variables Tools and Measurement

3 TYPES OF INVESTIGATIONS DESCRIPTIVE COMPARATIVE EXPERIMENTAL

DESCRIPTIVE Measure, observe and describe the subject of study Ex. Behavior among wolves in a pack

COMPARATIVE Comparing two or more things Ex. Heart Attack Rate in Men and Women

EXPERIMENTAL Controlled experiment to test a variable Ex. Effect of fertilizer on plant growth

A sequence of steps that you follow to conduct an investigation. Scientific Method A sequence of steps that you follow to conduct an investigation.

SCIENTIFIC METHOD OBJECTIVE- The question or problem RESEARCH-Gathering background information HYPOTHESIS- Prediction based on background info EXPERIMENT- Observing, measuring and recording data RESULTS- The data you collect and analyze CONCLUSION- The claim, evidence and reasoning

SCIENTIFIC QUESTIONS WITEOBOB=What is the effect of blank on blank? (the IV-the one thing the scientist changes) on (the DV-thing that responds to the thing the scientist changed and is measured and recorded as data)?

VARIABLES- Things in an experiment that can change or vary Independent Variable (IV) What the scientist manipulates to see if it causes a change The “cause” Dependent Variable (DV) The “effect” that is measured and recorded

OTHER PARTS OF AN EXPERIMENT CONSTANTS The things that are kept the same throughout the experiment Makes sure that the IV is the only reason for changes observed in the DV CONTROL The group in an experiment that does not experience a change in the IV The “normal” state that you can compare to

Example: Objective What is the effect of amount of fertilizer on plant growth? Independent Variable (IV) Amount of fertilizer Dependent Variable (DV) Plant Growth Control Plants that did not get fertilizer Constants Same soil and same amount of water, sunlight

Example: Objective What is the effect of antibiotic dose on the growth of pneumonia bacteria? IV= Different amounts of antibiotic drug DV= The “kill zone” around the antibiotic Control= a petri dish with pneumonia cells and no antibiotic Constants = the temperature, light, food source and the amount of time the petri dish is allowed to sit

SCIENTIFIC MEASUREMENT TOOL MEASUREMENT UNIT EXAMPLE METRIC RULER DISTANCE KILOMETER (km) METER (m) CENTIMETER (cm) MILLIMETER (mm) 9 football fields Length of a table Width of a pinkie Thickness of a dime GRADUATED CYLINDER LIQUID VOLUME MILLILITER (mL) 10 drops of water TRIPLE BEAM BALANCE MASS Kilogram (kg) Gram (g) Dictionary Paper Clip or TicTac L x W x H SOLID VOLUME (of a box or cube) Cubic Centimeters (cm3) A sugar cube

Measurement Practice = 1 cm and 4 mm = 1.4 cm or 14 mm = 27.7 g = 66 mL