Study Questions for Bio 101
Cellular Respiration
1. What is the ultimate purpose of catabolic reactions like cellular respiration? What is
the delta G of cell respiration --- is it exergonic or endergonic overall? Is it an oxidative
or reductive process?
2. What does it mean to say that glucose is oxidized? What are the products of
oxidation? How are these products transported around the cell? What are these
products used for?
3. Describe the function of nicotinamide adenine dinucleotide (NAD+) and flavin
adenine dinucleotide (FAD+) and how they can be oxidized and reduced. How are
these two molecules written when they are reduced? Exactly how do they carry
electrons?
4. Name the three parts of cellular respiration and write a general chemical equation for
part. Where in a prokaryotic cell is each process performed? Where in a eukaryotic
cell is each process performed?
5. Describe the process of glycolysis with regards to the starting molecule, ending
molecule(s), and the other reactants used and products produced. How many carbons
are in the product molecule? How many ATP are invested? How many net ATP are
produced overall? By what mechanism are these ATP produced? How many carbons
are in the product molecule?
6. What is Coenzyme A (CoA) and where does it play a part in cellular respiration?
7. When pyruvate is converted to an acetyl group, what two things are produced in this
reaction?
8. Write the overall equation for the Krebs Cycle, including the pyruvate to Acetyl CoA
step. How many NADHs are produced per pyruvate? Per glucose? How many
FADHs are made per pyruvate? Per glucose? How many carbon dioxide molecules
are released per pyruvate and per glucose? How many ATP made, and by what
phosphorylation process?
9. How many ATP are made by substrate level phosphorylation) )per glucose in
glycolysis? In the Krebs Cycle? Where is most of the energy from the glucose
molecule stored after it has been fully oxidized to carbon dioxide?
10. Which electron carrier holds electrons in very high energy states, NADH or FADH2?
How does this difference effect how these carriers release their "loads" to the electron
transport chain? How many protons are pumped by NADH electrons? FADH2
electrons? How many ATP are made per NADH? How many per FADH2?
11. Explain why electrons "flow" between the membrane proteins in the electron
transport chain. What drives this flow? How is this flow coupled to proton pumping?
12. Where do electrons go at the end of the electron transport chain in aerobic organisms?
What is the general name for this ultimate receiver of electrons? In anaerobic
bacteria, the "ultimate receiver" molecules are different ---what are they? What
molecules are formed when the "ultimate receiver" is reduced?
13. Describe the structure and function of the ATP synthetase. Where is it located in
mitochondria? Where is the F1(stem) and F0 (ball) part located? How many protons
are needed to drive the condensation of ADP and Pi?
14. Why are anaerobic conditions a problem for aerobic organisms? How do these
conditions affect the different parts of cellular respiration, and in what order are they
affected? Why?
15. How does fermentation solve the problems imposed by anaerobic conditions? Does
fermentation create the same results? What is the difference between alcoholic
fermentation and lactic acid fermentation, and what types of cells do which? How is
the rising of bread, the making of beer and yogurt, and the development of muscular
pain related to fermentation?
16. What other types of molecules other than glucose can be used to create ATP? How
are these alternate fuels incorporated into cellular respiration?
17. Where are the key points of control for the cellular respiration process? Which
enzymes are affects at which points?
18. List the following molecules in order of energy level according to the way they are
used in cellular respiration: NADH, H2O, CO2, ATP, FADH2, C6H12O6, pyruvate,
Acetyl CoA