In-Depth Look at Scientific Method
IA. How do scientists make observations? Using our? senses
1A. Make observations by using tools
II Identify the problem Write the problem in: A. Question form Ex. Does a plant grow in a closet?
Formulate a Hypothesis An educated guess A. Based on: observations B. Written in an “if/then” format Ex: If I grow a plant in a closet, then….
IIIC. To be able to perform an experiment, it must be Testable A lab experiment that can yield an answer
Examples: Can you test how far you can run on Mars?________ Testable?_____ Can you test how fast you can run a mile?_______ Testable?_______
D. After a hypothesis is shown to be reliable, it is considered to be: A theory
E. A factual hypothesis over time can become a….. Law = A scientific truth that cannot change Law of the cell Cells are the basic building block of life
F. This differs from a…. Theory = Proposed explanation of many experiments Not definite Can be changed Ex. Theory of Evolution
IV. Design and Carry Out Experiment A. Control Group The experiment performed with no changes – what you normally see Example: a plant growing in the window
B. Experimental Group/Variable One change to the experiment Example: putting the plant in the closet Same amount of soil, water, plant
C. Variable Any possible change to the experiment Putting plants in closet Vs window
D. Independent Variable Same as experimental group Changing one thing Ex. Putting the plant in the closet Graphed on the X axis
D. Dependent Variable What you are measuring – end result Growth of plant in centimeters Graphed on Y axis
V. Collect and Analyze data Collection of facts
Quantitative Observations # of something Ex. # of teeth? 32
Qualitative Observations Physical feature Ex: “red” Gatorade
VI. A. Draw Conclusions A. Prove or disprove hypothesis? B. Why??? Need data!!! C. Ex. The plant in the window grew 4 inches and the plant in the closet grew 2 inches.
Form a new hypothesis if… Hypothesis is incorrect Do experiment again Said that plant in closet would grow more – didn’t