Name _______________________________________
Period _____ Date __________
Cellular Respiration Lab
Question: How does exercise affect disposal of wastes (i.e. CO2) from cellular respiration?
Materials
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1 small beaker
Graduated cylinder
Bromothymol blue solution
2 straws
Clock or watch with a second hand (yes, you can use your phone for this).
Procedure
1. Put 10 mL of water and 3 drops of bromothymol blue solution into each test tube. Carbon dioxide (CO2) causes
bromothymol blue to turn yellow or green.
2. Place a straw into the bromothymol blue solution.
3. When your partner says “go”, slowly and gently blow air through a straw into the bottom of your beaker. Your
partner should start timing when he/she says “go”.
4. CAUTION: DO NOT INHALE THROUGH THE STRAW!
5. When the solution changes color (either to green or yellow), your partner should say “stop”, and record how
long it took for the color to change.
6. Jog in place for 1 minute. CAUTION: Do not do this if you have a medical condition that interferes with exercise.
If you feel faint or dizzy, stop immediately and sit down.
7. When your partner says “go”, slowly and gently blow air through a straw into the bottom of your beaker. Your
partner should start timing when he/she says “go”.
8. When the solution changes color (either to green or yellow), your partner should say “stop”, and record how
long it took for the color to change.
9. Pour the solution into the skin while water is running. If the solution gets on your skin, run water over the area
and wash it off.
10. Trade roles with your partner. Repeat steps 1-9.
Hypothesis
Record your prediction of how exercise will affect your body’s production of carbon dioxide. Remember to write it as an
“if, then” statement.
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Data
Test 1: (Your Name) _________________________________________________________________________________
Resting Rate
Color Change
Time
Rate with Exercise
Test 2: (Your partners name) __________________________________________________________________________
Resting Rate
Rate with Exercise
Color Change
Time
Graph your results
Analysis:
1. Explain the data.
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2. What was the dependent variable?
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3. What was the independent variable?
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4. What was the control? Did you have one?
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5. What were the constants?
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Conclusion:
1. Was your hypothesis supported? Why or why not?
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2. How did exercise affect the time for the solution to change color?
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3. What processes in your body produces carbon dioxide?
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4. Did you make any mistakes that could be corrected next time?
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5. What else would you want to know about this topic?
REINFORCEMENT : Fill in the chart and answer the following questions.
WORD BANK
1 ATP
2 ATP
36 ATP
4 NADH
1 FADH
Electron transport chain
Mitochondrion
Cytoplasm
Fermentation
Glycolysis
Glucose
Pyruvate
Lactic acid
Kreb's Cycle
Photosynthesis
Cellular Respiration
Organelle for process
Reactants
CO2 + H2O
Electron Transport Chain (located)
Cycle of Chemical Reactions
Calvin cycle (does what?)
Krebs cycle (does what?)
Products
1. What types of carbon-based molecules are most often broken down to make ATP? Explain how ATP production
differs depending on the type of carbon-based molecule that is broken down.
2. How does glycolysis contribute to the overall process of cellular respiration?
3. Write the chemical equation for cellular respiration and explain what it represents.
4. What is the function of the Krebs cycle? In your answer, describe the products of the Krebs cycle and what
happens to them.
5. Explain the function of the electron transport chain in cellular respiration. Why is oxygen needed for the
electron transport chain?
6. Fermentation does not produce ATP. Why is fermentation such an important process in cells?
7. How is alcoholic fermentation similar to lactic acid fermentation? How is it different?
8. In what organelle does the process of cellular respiration take place?
9. Do animals undergo cellular respiration? Do plants? Why/why not?