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AP Cell Respiration

When you click Submit (at the bottom of this web page) it will save your work on the server for me. If you get a "proxy error" hit -refresh- until you get a "Thanks"

You might want to actually write your answers in Word (so you can spell check them) and then cut-and-paste into the boxes. That way, if the computer misplaces your work you can just re-paste the answers.

Since we may work on this over more than one day, and you can work at home, I will keep track of what you have done. Feel free to click submit as you work to save your work to the server. I have however tried to keep the size of the assignment small enough that you should be able to do it in one session.

TAB OR USE THE MOUSE Between the fields....

Answer the questions as best you can. The boxes will expand as you type if you need more space. (Don't worry if it is a one word answer. The box size is standard.)

Since you will be working in groups, put all the names of the people in the group in the box. The ideal group size is 2. As an exception I will allow groups of 3. No groups of 4 or 5. If you work as a group of 3 I expect better answers. Group sizes above 3 will be penalized in the grading.


Class Period

1 2 3 4 5 6  7 8

Click on the link below, and switching between this document and the open browser answer the questions. Most of the answers can be found through observation, but some require thought or research on the web.

Spend a couple of minutes “playing” at each site to figure out how it works. Some have an audio track, and I'd REALLY appreciate it if you used headphones.

Cell Respiration Computer Activity

This site looks at the "missing step" in cellular respiration. 

Question 1: How much ATP is made directly (substrate level phosphorylation) in this missing step? How much ATP is made indirectly (as a result of reduced intermediates) from this step?


This is a College Biochemistry site.

Don't get bogged down in the detail. I do not expect you to know the molecules, but make sure you understand the "gist" of what is going on.

Don't worry about the sorting step, just "continue."

Question 2:  What are the products of the citric acid cycle? What is meant by "reducing power?"

Oxidative Phosphorylation


Question 3:  Now, why are membranes important???? What would happen if small holes developed in the mitochondrial inner membrane that allowed a back flow of hydrogen ions?

How many protons (count carefully) are pumped across for each NADH (2 electrons)?  Why does FADHproduce less ATP than NADH (be explicit!)?


Question 4: Is there a direct linkage between the TCA cycle and oxidative phosphorylation? Explain. 


Question 5: Compare substrate level phosphorylation to oxidative phosphorylation. 


Question 6: Did these animations help? Which site did you find the most useful?. 



This web page is being hosted at Dr. Gottfried's  Tripod account. Technical questions should be referred to