# Experimental Design Scenarios #2

```Biology
Scientific Method
Name ________________________
Date __________ Period________
Scientific Method
Scenario #1
In chemistry class, Allen wanted to determine the effectiveness of various metals in
releasing hydrogen gas from hydrochloric acid. Several weeks later, Allen read that a
utilities company was burying lead next to iron pipes to prevent rusting. Allen
hypothesized that less rusting would occur with the more active metals. He placed the
following into separate beakers of water: (a) iron nail (b) 1 iron nail wrapped in an
aluminum strip (c) 1 iron nail wrapped with a lead strip and (d) 1 iron nail wrapped with
a magnesium strip. He used the same amount of water, equal amounts (mass) of the
metals, and the same type of iron nails. At the end of 5 days, he rated the amount of
rusting as small, moderate, or large. He also recorded the color of the water.
Hypothesis:______________________________________________________________
Prediction (If…then)_____________________________________________________
_______________________________________________________________________
Independent variable: ______________________________________________________
Dependent variable: _______________________________________________________
Data types: Qualitative or Quantitative
Control: ________________________________________________________________
Constants: ______________________________________________________________
Scenario #2
Joanna wanted to know what type of running shoes held up the best over time. She
purchased 5 different brands (Nike, Addidas, Under Armor, Sketchers, and ACIS.) She
wore and ran in each brand of shoe for the same amount of miles over a given year. All
experiments were conducted on the same type of day when the weather conditions were
similar, e.g. air, temperature, and wind. She then measured the distance that the tread on
the shoes decreased.
Hypothesis: ____________________________________________________________
Prediction: (If…then)_____________________________________________________
_______________________________________________________________________
Independent variable: ______________________________________________________
Dependent variable: _______________________________________________________
Data types: Qualitative or Quantitative
Control: ________________________________________________________________
Constants: ______________________________________________________________
Scenario #3
Tyler wanted to know if sharks are more active if the water temperature in their habitat
increased. At work as a marine scientist at the Baltimore Aquarium, he increased the
tank’s water temperature by five degrees each day for one week and recorded the shark’s
behavior.
Hypothesis: _____________________________________________________________
Prediction: (If…then)_____________________________________________________
_______________________________________________________________________
Independent variable: ______________________________________________________
Dependent variable: _______________________________________________________
1
Data types: Qualitative or Quantitative
Control: ________________________________________________________________
Constants: ______________________________________________________________
Scenario #4
Jackie read that Aloe vera promoted healing of burned tissue. She decided to investigate
the effect of varying amounts of Aloe vera on the regeneration of planarian. She bisected
the planarian to obtain 10 parts (5 heads and 5 tails) for each experimental group. She
applied concentrations of 0% (no aloe vera), 10%, 20%, and 30% Aloe vera to the group.
Fifteen mL of Aloe vera solutions were applied. All planarian were maintained in a
growth chamber with identical food, temperature and humidity. On Day 15, Jackie
observed the regeneration of the planarian parts and categorized them as full, partial, or
none.
Hypothesis: _____________________________________________________________
Prediction: (If…then)_____________________________________________________
_______________________________________________________________________
Independent variable: ______________________________________________________
Dependent variable: _______________________________________________________
Data types: Qualitative or Quantitative
Control: ________________________________________________________________
Constants: ______________________________________________________________
Scenario #5
Taylor was curious and wanted to know which battery types lasted longest in his
television controller. He bought 3 different types of batteries and placed each set into his
remote respectively and then tracked how long it took for them to die.
Hypothesis: _____________________________________________________________
Prediction: (If…then)_____________________________________________________
_______________________________________________________________________
Independent variable: ______________________________________________________
Dependent variable: _______________________________________________________
Data types: Qualitative or Quantitative
Control: ________________________________________________________________
Constants: ______________________________________________________________
Scenario #6