Yeast Respiration Lab
Question:
What conditions are necessary for Respiration to occur in
Yeast?
Materials:
• Large Test Tubes or 50 ml plastic bottles
• teaspoon
• yeast
• sugar packets
• gatorade
• diet coke
• balloons
• 50 ml graduated cylinder
Procedure:
1. Label seven bottles A, B, C, D, E, F, G
2. Add ½ teaspoon yeast to bottle A—F
3. Set up bottles and cover tightly with a balloon
a. Bottle A: 36 mL water
b. Bottle B: 36 mL water + 1 sugar packet
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c. Bottle C: 36 mL water + 2 sugar packets
d. Bottle D: 18 mL water + 18 mL gatorade
e. Bottle E: 36 mL gatorade
f. Bottle F: 18 mL water + 18 mL diet coke
g. Bottle G: 36 mL water only (no yeast)
4. Observe what happens inside the bottle and to balloon
at 30 minutes and 24 hours.
5. Complete the data table below.
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Table 1.1: Observations
Bottle
Inside
Bottle
30 minutes
Diameter (cm)
Inside
Bottle
24 hours
Diameter
A
B
C
D
E
F
G
6. Create a graph of time vs. diameter. Plot a line for
each flask using different colored pencils or use excel
to create the graph.
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Conclusion Questions
1.
2.
3.
What were you trying to determine by doing this
experiment?
Identify positive and negative controls.
Describe your results and explain what you found out
about cellular respiration at 30 minutes and 24
hours.
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4.
5.
What gas was produced as a result of respiration?
What is the source of energy used for respiration, if
any, for each experimental condition.
A
B
C
D
E
F
G
6.
In order to make good homemade bread, cellular
respiration must occur. The CO2 produced allows the
bread to be light and airy. What ingredients would
you need to include in your recipe?
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