Name: __________________________________________________________________________ Period: _____
Yeast Respiration Virtual Lab
Purpose: This virtual investigation are will allow you to compare the processes of aerobic and anaerobic respiration in
order to better understand the similarities and differences between these two processes.
Procedure: Go to the Virtual Investigation for Chapter 4 on the Holt-McDougal website at http://my.hrw.com
Remember that your user name is your school email and your password is (mihs.your id number). Once you are logged
in, select the online textbook. Then from the top menu bar, select Chapter 4 and in the student premium version (See
screenshot below) and enter go. Under the multimedia labs and activities tab select the Chapter 4 Photosynthesis and
Cellular Respiration virtual investigation.
You must be in the
Student Premium Tab.
Select Chapter 4 and
Click “GO”
First watch the animation of the photosynthesis and cellular respiration and answer the questions below. Have the
sound off and read the captions or use headphones.
1.
What is the role of NADH, NADPH, and FADH2?
2. How is O2 produced in the light reactions of photosynthesis?
3.
What type of organisms might rely on the energy released in glycolysis as their only source of energy? (Give an
example of this type of organism)
4.
What would cause the electron transport chain and the Krebs cycle (processes that produce more ATP from the
energy stored in a sugar) to stop?
5.
Lactic acid fermentation and alcohol fermentation don’t produce additional ATP after glycolysis. Why do
organisms perform these processes under anaerobic (no oxygen) conditions?
After watching the animation of photosynthesis and cellular respiration, follow the directions for the virtual
investigation. Before you run the final step in the experiment, fill in the hypothesis columns in the table below for the
end results. Show your teacher your hypothesis, explain why you are making these predictions and get a signature
before you proceed with the investigation.
Hints for your hypotheses:








All the flasks have yeast
Flask A has no glucose and no oxygen
Flask B has oxygen but no glucose
Flask C has glucose but no oxygen
Flask D has both glucose and oxygen
Yeast is NOT an autotroph and is NOT able to perform photosynthesis.
Yeast is an organism that can perform both anaerobic fermentation if oxygen is not present and aerobic
respiration if oxygen is present.
Reflect on the reactants that would be required for either of those processes, the products if either
process if it is occurring, the purpose (to release the energy in food to create ATP), and the different
outcomes of anaerobic vs. aerobic.
Your predictions do not have to be set numbers (except for values that you predict will remain or decrease to 0). You
could predict the amount of each substance will increase or decrease or state whether the amount will be high or low.
Teacher’s signature: ___________________________________________________
Complete the investigation and fill in the actual results.
Culture
Atmosphere
Glucose
Start
actual
A
No O2
B
O2
present
No O2
C
D
O2
present
Glucose
End
Hyp.
actual
ATP
Start
actual
ATP
End
Hyp.
actual
CO2
Start
actual
CO2
End
Hyp.
actual
Ethanol
Start
actual
0
0
0
0
0
0
0
0
50
0
0
0
50
0
0
0
Ethanol
End
Hyp.
actual
Fill in your answers to the following questions on the website, then check your answers and put the correct answers to
the questions below.
1. Which culture(s) lack a source of energy?
A __
B __
C __
D __
2. Which culture(s) represent cellular respiration?
A __
B __
C __
D __
3. Which culture(s) represent aerobic respiration?
A __
B __
C __
D __
4. Which culture(s) represent anaerobic respiration?
A __
B __
C __
D __
5. Which culture released the most energy?
A __
B __
C __
D __
6. Which culture could be used to make bread dough rise?
A __
B __
C __
D __
7. Which culture could be used to make wine from grape juice?
A __
B __
C __
D __
Answer the following questions regarding the cultures:
1. Using the answer from number 4 above, circle whether anaerobic respiration or did not occur in each of the
flasks, provide evidence of how you know this and explain why it did or did not occur.
In flask A, anaerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask B, anaerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask C, anaerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask D, anaerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
Using the answer from number 3 above, circle whether aerobic respiration or did not occur in each of the flasks,
provide evidence of how you know this and explain why it did or did not occur.
In flask A, aerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask B, aerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask C, aerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
In flask D, aerobic respiration did/did not occur
evidence________________________________________________________________________________
reason__________________________________________________________________________________
2.
What does the presence or absence of ethanol at the end of the investigation indicate?
3.
Compare the amount of carbon dioxide produced in alcohol fermentation vs. aerobic respiration.
4.
Explain why the flask that produced the most ATP from the glucose was able to do so.
5.
What was the purpose of flasks A and B that lacked glucose?