1. To what molecule is the acetyl group of acetyl CoA transferred in the first step of the citric acid cycle?
2. When amino acids undergo degradation in the liver, what is the first step of the process?
3. What is the location in the mitochondrion of the protein complexes responsible for oxidative phosphorylation?
4. Cytochromes are ___________________ and are located ____________________________.
5. Which of the following compounds inhibits the pyruvate dehydrogenase complex?
Acetyl CoA
ADP
GTP
NAD+
FAD
6. The oxidative reactions of metabolism provide for most ATP production. In what specific part of the cell do these reactions occur? (Points : 1)
Nucleus
Ribosome
Mitochondria
Mitochondrial membrane
None of the above
7. Which of the following substances serves as an intermediate through which all cellular energy sources are interconvertible? (Points : 1)
Acetyl CoA
Glucose
ATP
Pyruvate
Citrate
8. What is the terminal electron acceptor in aerobic organisms?
Cyanide
NAD+
FAD
Oxygen
Carbon dioxide
9. What is another name for the F0F1 complex involved in oxidative phosphorylation?
NADH
Mitochondria
Cristae
Transport proteins
ATP synthase
10. How many molecules of FADH2 are produced by the complete oxidation of one acetyl group by the citric acid cycle?
1
2
4
6
12
11. In addition to carbon dioxide, ATP and water, what other reactant is involved in the first step of the urea cycle?
Urea
Citrulline
NAD+
NH4+
Pi
12. Cells in fast twitch muscle fibers contain more mitochondria than do cells in slow twitch fibers.
False
13. What compound, in addition to glutamate, is produced in the transamination reaction in which alanine and a-ketoglutarate react?
Acetyl CoA
Lactate
Glycerol
Oxaloacetate
Pyruvate
14. In the first stage of amino acid degradation, the carboxylate group is removed as carbon dioxide.
True
False
15. The enzyme succinate dehydrogenase catalyzes the oxidation of succinate. What is the product of this reaction?
Oxaloacetate
Citrate
Fumerate
Malate
None of the above
16. What key role does the urea cycle play in the degradation of amino acids?
Remove ammonium ions from blood
Remove ammonia molecules from blood
Remove carbon monoxide from the blood
Remove glucose from the blood
None of the above
17. In acetyl coenzyme A, the atom to which the acetyl group derived from pyruvate is bonded is:
N
Co
Cl
S
P
18. What word is used to describe a pathway that functions in both degradative and biosynthetic reactions?
Catabolic
Anabolic
Metabolic
Amphibolic
Diabolic
19. A deficiency of urea cycle enzymes causes an elevation of the ammonium ion concentration. )
True
False
20. How many cycles of the citric acid cycle are required to completely oxidize all the pyruvate formed when a molecule of glucose undergoes glycolysis?
2
3
4
5