A. the citric acid cycle
B. the conversion of pyruvate to lactic acid
C. the conversion of pyruvate to acetyl-CoA
D. the conversion of pyruvate to ethanol
2. Which of the following is true about the fermentation of glucose?
A. It can occur under aerobic or anaerobic conditions, depending on the products generated.
B. There is no net yield of ATP.
C. The hydrogen to carbon ratio (H:C) of the reactants and products remains the same.
D. It always generates CO2.
3. Glycogen is degraded in a
A. phosphorylation reaction.
B. hydrolysis reaction.
C. dephosphorylation reaction.
D. phosphorolysis reaction.
4. Which of the following sugars does not get converted to D-glucose before entering the glycolytic pathway?
A. D-galactose
B. glycogen
C. sucrose
D. lactose
5. Which of the following steps occurs during the payoff phase of glycolysis?
A. the conversion of phosphoenolpyruvate to pyruvate
B. the conversion of fructose 6-phosphate to fructose 1,6-biphosphate
C. the conversion of glucose 6-phosphate to fructose 6-phosphate
D. the conversion of glucose to glucose 6-phosphate
6. Under what conditions will lactic acid accumulate in skeletal muscle?
A. when citric acid enzymes are depleted
B. when ATP is depleted
C. when O2 is depleted
D. when NADH is depleted
7. The enzyme that converts 3-phosphoglycerate to 2-phosphoglycerate is a
A. transferase.
B. kinase.
C. mutase.
D. phosphorylase.
8. Glycolysis and the pentose phosphate pathway are the same in that
A. they both generate NADPH.
B. they both generate ATP.
C. they both involve the oxidation of glucose.
D. they are reversible.
9. Which of the following reactions is catalyzed by transaldolase?
A. xylulose 5-phosphate + ribose 5-phosphate
glyceraldehyde 3-phosphate + sedoheptulose 7-phosphateB. ribose 5-phosphate
xylulose 5-phosphateC. sedoheptulose 7-phosphate + glyceraldehyde 3-phosphate
erythrose 4-phosphate + fructose 6-phosphateD. xylulose 5-phosphate + erythrose 4-phosphate
glyceraldehyde 3-phosphate + fructose 6-phosphate10. What is the role of uridine diphosphate (UDP) in the conversion of galactose to glucose 1-phosphate?
A. Its hydrolysis is needed to provide the energy to convert galactose to glucose 1-phosphate.
B. It donates a phosphoryl group to galactose to generate galactose 1-phosphate.
C. It serves as a phosphate acceptor.
D. It serves as a carrier for galactose and glucose.
11. The NADPH produced in the pentose phosphate pathway is used
A. to donate electrons to O2 in mitrochondria.
B. to provide reducing power for biosynthetic reactions.
C. to convert superoxide free radicals (·O2-) into hydrogen peroxide (H2O2) during detoxification.
D. to provide the energy for catabolic reactions.
12. Which of the following is true about gluconeogenesis?
A. In mammals, gluconeogenesis occurs predominately in the liver.
B. Gluconeogenesis is the pathway by which glucose is converted to glycogen.
C. The gluconeogenesis pathway is the glycolysis pathway running in the opposite direction.
D. Plants do not undergo gluconeogenesis.
13. Rapidly dividing cells have a high need for nucleotide precursors, which are provided by
A. the Cori cycle.
B. the pentose phosphate pathway.
C. glycolysis.
D. gluconeogenesis.
14. All of the bypass reactions used in gluconeogenesis
A. require high-energy equivalents.
B. involve the removal of phosphate groups.
C. are irreversible.
D. requires mitochondrial enzymes.
15. Mammals cannot convert fatty acids to glucose because
A. they have no pathway for breaking down fatty acids.
B. they cannot use pyruvate as a precursor of glucose.
C. the glycolysis pathway is not reversible.
D. they cannot convert acetyl-CoA to pyruvate.
sources: Lehninger's principle of Biochemistry
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