Louis Pasteur’s Lab rePort
Name : _______________________
A. Purpose/Question: Is there a life force in air?
B. Initial Observations made by Pasteur:
It is known that broth exposed to air spoils – bacteria grows in it. But a
container of soup that is boiled for one hour and then sealed remains
sterile.
C. Hypothesis
D.
1.
2.
3.
Procedure:
Place broth in flask with straight neck and flask with bent neck.
Boil the broth in both flasks for one hour.
Allow flasks to sit for 24 hours, then observe.
E. Results: Data Table:
Flask with straight neck
Flask with bent neck
Start
Sterile (no bacteria present)
Sterile (no bacteria present)
After 24 hours
F. Observation:
When the flask with the bent neck was tilted so the broth touched the
top/middle of the neck, the broth became cloudy with bacteria.
G. Conclusion:
H. Discussion:
1. Identify the control
2. Identify the independent (manipulated) variable
3. Identify the dependent (responding) variable
You can draw a picture if you would like.