Transpiration Lab

Margaret Bahe’s Transpiration Lab
Purpose: To determine how transpiration affects plants under various conditions.
Hypothesis: _________________________________________________________________
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Experiment
Materials:
o Small Plastic Bags
o String
o Labeling Tape
o Markers
o Spray Bottle
o Fan
o Flood Light
o Balance
o Bedding Plants that are moist
Methods:
1. Select 4 plants. Remove any blooms present. Any blooms or leaves that fall off during
the week should be placed back in the center of the plant so as not to affect mass.
2. Carefully wrap the root ball of each plant in a small plastic bag.
3. Tie the bag snuggly around the stems with the string.
4. Mist one plant well with water and cover with another plastic bag and secure with the
string. Label as HIGH HUMIDITY
5. Label the others as: CONTROL, FAN, and LIGHT
6. Record the masses of each of the four plants.
7. Place each of the four plants in the appropriate location in the room
a. CONTROL – adequate light with no draft
b. FAN – adequate light with a fan one meter from the plant and left on low
c. LIGHT – place lamp one meter from plants with a heat sink between them.
d. HIGH HUMITIDY – adequate light
8. Record the masses of the plants each day for one week.
9. Plot the change in mass for all plants on a graph.
Independent Variable:________________________________________________________
Dependent Variable __________________________________________________________
Control: ____________________________________________________________________
Safety:
1. _______________________________________________________________________
2. _______________________________________________________________________
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Observations:
Type
Plant
Monday Tuesday Wednesday Thursday Friday
Control
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Fan
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
High
Humidity
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Light
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
Cum g =
(%) Cum =
2

Discussion:
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Conclusion:
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