Generating Hypotheses & Experimental Design Worksheet Form (Page 2 of 2) in pdf

Name _____________________________

AP Biology

3. Experimental Design

a. Which is your measured (dependent) variable? _______________________________

Example: height of plants (because I didn’t know how that was going to change

therefore I had to measure how its change was dependent on the amount of fertilizer).

b. Which is your manipulated (independent) variable? _____________________________

Example: amount of fertilizer (because I manipulated how much fertilizer was given; it

changed only how I chose it to change and was not dependent on any other factor in the

experiment)

c. List three confounding variables that you would have to control to isolate your tested

variable.

(Confounding means confusing, so confounding variables would be other factors that

could affect the results and therefore confuse your interpretation of the results)

Example: amount of water, type of soil, temperature, amount of light, age of plants…

_________________________________________________________________________

d. Describe the experimental groups for your experiment.

Example: each group of 10 plants is treated with a different amount of fertilizer: 0

tsp/gallon, ! tsp/gall, " tsp/gall, 1 tsp/gall (recommended), 2 tsp/gall, 4 tsp/gall

_________________________________________________________________________

e. Describe the control group(s) for your experiment.

Example: the group receiving only water (“standard” or no treatment condition)

_________________________________________________________________________

Suggest a sample size for your test groups in this experiment. ____________________

Example: just NOT one plant; consider at least 10 or more per group

g. What result would cause you to conclude that your hypothesis is supported?

Example: the plants that are given more fertilizer grow taller than the ones given less.

_________________________________________________________________________

h. What result would cause you to reject your hypothesis?

Example: the plants that are given more fertilizer do NOT grow taller than the ones

given less

_________________________________________________________________________

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Generating Hypotheses & Experimental Design Worksheet Form Page 2