Figure 2.4
Sample Biology Research Design Table
Hypothesis Draft
If the amount of solid surface on top of the soil is related to the strength of the seedling, then
seedlings will break through thinner surfaces more consistently and with less damage to the
seedling.
Independent Variable
Varying depth of solid
surfaces for seedlings to
grow through
Background Questions
What species of seeds would best be used?
What type of seed has a fast germination rate and is easy to
grow in controlled conditions?
What are the best solid surfaces to use? (Plaster of paris, concrete
mix, spackling paste?) What other variables might be introduced
by using these materials? How can I reduce those?
What are the best ways to measure “strength” of seedlings?
(Crack of surfaces, speed at which they get through the
surface?)
Dependent Variable
Quantitative
# of days it takes to
break through surface
width/length of the crack
Thickness of seedling stem
Qualitative
Condition of the seedling
during and after breaking
through surfaces
Conditions of roots and
seedling
Constants
Seedlings all have the same lighting, watering, and feeding
schedule (plants are rotated weekly).
Data collection is done at the same time every day.
Temperature of the room remains the same for all seedlings.
Seeds of the same kind came from the same package.
Seeds are all planted in the same type and size container (clear
plastic cup).
All seeds have the same quality and amount of soil underneath the
solid surface.
Experimental Groups and
Control Group
Control Group
No solid
surface
(just soil)
Exp. Group #1
.5 cm depth
solid surface
Exp. Group #2
1 cm depth
solid surface
Exp. Group #3
1.5 cm depth
solid surface