BIO 306
Review Questions
Chapter 25 – Part I
Cell Metabolism
1. Define the following:
a. metabolism
b. anabolism
c. catabolism
d. enzyme
e. energy of activation
f. hydrolysis reaction
g. substrate
h. product
i. reactant
k. metabolic pathway
l. energy
m. ketone body
2. Give an example of an anabolic reaction that occurs in the body.
3. Give an example of a catabolic reaction that occurs in the body.
4. Do all metabolic reactions require a certain amount of energy input to occur? If so, why?
5. Why are enzymes important in metabolism?
6. Give 3 characteristics of an enzyme.
7. What are 3 “environmental conditions” which can effect the activity of an enzyme.
8. Describe how changes in each of the above “environmental conditions” will effect the activity of an enzyme.
9. Define and differentiate between a “Cofactor” and a “Coenzyme”.
10. Why are cofactors and coenzymes important in metabolic reactions.
11. What is the First Law of Thermodynamics?
12. Define and differentiate between “Oxidation” and “Reduction”. (Remember LEO goes GER)
13. Give some of the general characteristics of anaerobic metabolism.
14. Which metabolic pathway(s) is/are involved in anaerobic metabolism?
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15. Give some of the general characteristics of aerobic metabolism.
16. Which metabolic pathway(s) is/are involved in aerobic metabolism?
17. What are the 2 mechanisms in which the body can produce ATP?
18. Define and describe the following processes:
a. Substrate Level Phosphorylation
b. Oxidative Phosphorylation
19. Concerning Glycolysis:
a. Where does it occur?
b. What is/are its beginning substrate(s)? How many carbon do/does this/these molecule(s) contain?
c. How much energy is required to start the pathway?
d. Which mechanism(s) is/are used to produce ATP in this pathway?
e. What is the “gross” number of ATP produced in this pathway?
f. What is the “net” gain of ATP in this pathway?
g. What is the final product of this pathway?
h. How many electron carriers are produced in this pathway? Are they NADH or FADH2?
I. What happens to electron carriers produced in this pathway?
j. How much CO2 is produced in this pathway?
20. Concerning Pyruvate
a. Where is it produced?
b. How many carbon atoms are in 1 molecule of pyruvate?
c. How many pyruvate molecules are produced from one molecule of glucose?
d. In animals, explain what happens to pyruvate if oxygen is present. Be specific and thorough.
e. In animals, explain what happens to pyruvate if oxygen is not present. Be specific and thorough.
21. Explain the importance of the reaction converting pyruvate to lactate.
22. Concerning the citric acid cycle:
a. Where does it occur?
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b. What is/are its beginning substrate(s)? How many carbon do/does this/these molecule(s) contain?
c. Which mechanism(s) is/are used to produce ATP in this cycle? Describe/Explain.
d. How many “trips” through this cycle can be fueled by 1 molecule of Acetyl CoA?
e. How many electron carriers are produced in this cycle? Are they NADH or FADH2?
f. What happens to electron carriers produced in this cycle?
g. How much CO2 is produced in this cycle?
hi. Which electron carriers are used in this cycle, and how many of each are produced?
i. How many “trips” through this cycle can be fueled by 1 molecule of glucose?
j. How many molecules of ATP will be produced from 1 molecule of Acetyl CoA, providing all of the electron
carriers proceed on through the electron transport chain?
k. Is oxygen required for this pathway to occur? EXPLAIN.
23. Concerning the Electron Transport Chain (ETC):
a. Where does it occur?
b. How many H+ are pumped across the membrane for each NADH molecule that ‘enters’ the ETC?
c. How many H+ are pumped across the membrane for each FADH2 molecule that ‘enters’ the ETC?
d. What is the name of the enzyme that is directly responsible for synthesizing ATP?
e. How does this enzyme (from d) use the H+ concentration to synthesize ATP?
f. Where is oxygen utilized, and specifically, what happens to it?
g. Describe the general workings of the ETC. Be specific and thorough.
h. What serves as the final “electron acceptor” in the ETC?
24. What happens in the ETC if the utilization of oxygen is blocked or prevented?
25. What are the 4 possible fates of ingested glucose (say from ingesting a pint of Ben and Jerry’s New York Super
Fudge Chunk…)?
26. What is the most common lipid consumed by humans?
27. Before energy can be obtained from a fat molecule, what must first happen to it?
28. What metabolic pathways are involved in the complete oxidation of a free fatty acid?
29. Concerning Beta Oxidation:
a. Where does it occur?
b. What is (are) its beginning substrate(s)? How many carbons does this molecule contain?
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c. How much energy is required for 1 “cycle/trip” through the pathway?
d. Is any ATP produced directly in this pathway?
e. What is the final product of this pathway?
f. How many electron carriers are produced in this pathway? Are they NADH or FADH2?
g. What happens to electron carriers produced in this pathway?
h. How much CO2 is produced in this pathway?
I. Is oxygen required for beta oxidation to occur? EXPLAIN.
30. Assume that you begin with a 6 carbon free fatty acid.
a. How many ATP molecules will be required in the beta oxidation pathway assuming maximal Acetyl CoA
production.
b. What is the maximal number of AcetylCoA molecules that can be produced by a 6 carbon Free Fatty Acid in
the
beta oxidation pathway?
c. How many molecules of NADH will be produced in the beta oxidation pathway? How many molecules of
FADH2?
d. Assuming that all of the electron carriers produced in beta oxidation) proceed through the ETC, and that all
Acetyl CoA molecules (from Beta Oxidation) proceed through the TCA cycle, what will be the net gain of
ATP
molecules from a 6 carbon free fatty acid?
31. List the 3 ketone bodies.
32. How are the majority of dietary proteins utilized by the body?
33. Explain what is meant by the term “deamination”.
34. What is urea, in general how is it made, and why is it important?
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