Questões Bioquímica (inglês)

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1. Which of the following statements correctly describes metabolism? 
 a. Fatty acids can be precursors of glucose 
 b. High energy levels turn on glycolysis 
 c. Synthesis and degradation of a substance do not occur at the same time 
 d. Phosphorylation activates enzymes that store fat and glycogen 
 e. Guanosine triphosphate (GTP) is the major donor for enzyme phosphorylation 
 
2. A compound normally used to conjugate bile acids is 
 a. Acetate 
 b. Glucuronic acid 
 c. Glutathione 
 d. Sulfate 
 e. Glycine 
 
4. The reactions leading to the synthesis of squalene (C30) from dimethylallyl pyrophosphate 
(C5) are 
 a. Sequential condensation of five-carbon units 
 b. Sequential condensation, then cyclization, of five-carbon units 
 c. Sequential condensation of five-carbon-pyrophosphate units 
 d. Sequential condensation of 5-carbon units to 15-carbon units, then condensation 
 of 15-carbon units 
 e. Sequential condensation of 5-carbon units to 10-carbon units, then sequential 
 condensation of 10-carbon units 
 
5. Which of the following involves isoprenoids? 
 a. The chromophore of visual pigments 
 b. Carnitine 
 c. Vitamin C 
 d. Thiamine 
 e. Ketone bodies 
 
6. Aspirin inhibits which of the following enzymes? 
a. Lipoprotein lipase 
b. Lipoxygenase 
c. Cyclooxygenase 
d. Phospholipase D 
e. Phospholipase A2 
 
7. Which of the following processes yields arachidonic (5,8,11,14-eicosatetraenoic) acid in 
mammals? 
a. Elongation of stearic acid 
b. Chain elongation and one desaturation of linolenic (9,12,15-octadecatrienoic) 
acid 
c. Chain elongation and two desaturations of linoleic (9,12-octadecadienoic) acid 
d. Desaturation of oleic acid 
e. Elongation of palmitic acid 
 
8. Which of the following is an essential fatty acid? 
a. Palmitic acid 
b. Linoleic acid 
c. Arachidonic acid 
d. Oleic acid 
e. Eicosatetraenoic acid 
 
9. Which of the following compounds serves as a primary link between 
the citric acid cycle and the urea cycle? 
a. Malate 
b. Succinate 
c. Isocitrate 
d. Citrate 
e. Fumarate 
 
10. Which one of the following can be converted to an intermediate of 
either the citric acid cycle or the urea cycle? 
a. Tyrosine 
b. Lysine 
c. Leucine 
d. Tryptophan 
e. Aspartate 
 
11. Most major metabolic pathways are considered to be either mainly 
anabolic or catabolic. Which of the following pathways is most correctly 
considered to be amphibolic? 
a. Lipolysis 
b. Glycolysis 
c. β oxidation of fatty acids 
d. Citric acid cycle 
e. Gluconeogenesis 
 
12. Which one of the following products of protein metabolism is 
decreased below normal levels during the early stages of starvation? 
a. Urea 
b. Anabolic enzymes 
c. CO2 
d. NH4+ 
e. Glucose 
 
 
 
 
 
 
 
 
13. Which one of the following is a correct statement about the regulation 
and sequence of reactions in metabolic pathways? 
a. The initial step in many pathways is a major determinant of control 
b. The sequence of steps in catabolic pathways is usually the exact reverse of the 
biosynthetic sequence 
c. Enzymes found in an anabolic pathway are rarely found in the corresponding 
catabolic pathway 
d. A small set of large precursors serves as the starting point for most biosynthetic 
processes in energy metabolism 
e. Steps in both anabolic and catabolic pathways are usually irreversible 
 
14. Which one of the following statements is correct regarding the wellfed 
state? 
a. NADPH production by the hexose monophosphate shunt is decreased 
b. Acetoacetate is the major fuel for muscle 
c. Glucose transport into adipose tissue is decreased 
d. The major fuel used by the brain is glucose 
e. Amino acids are utilized for glucose production 
 
15. During an overnight fast, the major source of blood glucose is 
a. Dietary glucose from the intestine 
b. Hepatic glycogenolysis 
c. Gluconeogenesis 
d. Muscle glycogenolysis 
e. Glycerol from lipolysis 
 
16. Approximately 3 h following a well-balanced meal, blood levels of 
which of the following are elevated? 
a. Fatty acids 
b. Glucagon 
c. Glycerol 
d. Epinephrine 
e. Chylomicrons 
 
17. If a homogenate of liver cells is centrifuged to remove all cell membranes 
and organelles, which of the following enzyme activities will remain 
in the homogenate? 
a. Glucose-6-phosphate dehydrogenase 
b. Glycogen synthetase 
c. Aconitase 
d. Acyl CoA hydratase 
e. Hydroxybutyrate dehydrogenase 
 
 
 
 
 
18. Which of the following enzymes is active in adipocytes following a 
heavy meal? 
a. Glycogen phosphorylase 
b. Glycerol kinase 
c. Hormone-sensitive triacylglyceride lipase 
d. Glucose-6-phosphatase 
e. Phosphatidate phosphatase 
 
19. Which of the following statements correctly describes insulin? 
a. It is an anabolic signal to cells that glucose is scarce 
b. It is converted from proinsulin to insulin primarily following secretion from β 
cells 
c. It does not have a prohormone form 
d. It is a small polypeptide composed of a single chain bridged by disulfide groups 
e. Its action is antagonistic to that of glucagon 
 
20. Lack of glucocorticoids and mineralocorticoids might be a consequence 
of which of the following defects in the adrenal cortex? 
a. Androstenedione deficiency 
b. 17α-hydroxyprogesterone deficiency 
c. Estrone deficiency 
d. C-21-hydroxylase deficiency 
e. Testosterone deficiency 
 
21. Epinephrine stimulation of lipolysis in adipocytes is thought to differ 
from epinephrine stimulation of glycogenolysis in the liver in which way? 
a. Glucagon, not epinephrine, stimulates lipolysis in adipocytes 
b. The mechanism of hormone-receptor interaction is thought to be fundamentally 
different in each tissue 
c. Phosphorylase kinase is activated directly by a second messenger in adipocytes, 
but not in the liver 
d. Adenosine 3′,5′-cyclic monophosphate (cyclic AMP) is the second messenger 
in adipocytes, but not in the liver 
e. Only protein kinase is interposed as an amplification factor between the second 
messenger and the physiologically important enzymes in adipocyte 
 
22. Pantothenic acid is important for which of the following steps or 
pathways? 
a. Pyruvate carboxylase 
b. Fatty acid synthesis 
c. Pyruvate carboxykinase 
d. Gluconeogenesis 
e. Glycolysis 
 
 
 
 
23. Which of the following vitamins can act without phosphorylation? 
a. Pyridoxine 
b. Lipoamide 
c. Niacin 
d. Thiamine 
e. Riboflavin 
 
24. Which of the following vitamins becomes a major electron acceptor, aiding in the oxidation 
of numerous substrates? 
a. Vitamin B6 
b. Niacin 
c. Riboflavin 
d. Thiamine 
e. Vitamin B1 
 
25. Which of the following conditions most rapidly produces a functional deficiency of vitamin 
K? 
a. Coumadin therapy to prevent thrombosis in patients prone to clot formation 
b. Broad-spectrum antibiotic therapy 
c. Lack of red meat in the diet 
d. Lack of citrus fruits in the diet 
e. Premature birth 
 
26. Which of the following statements regarding vitamin A is true? 
a. Vitamin A promotes maintenance of epithelial tissue 
b. Vitamin A is necessary for hearing but not for vision 
c. Vitamin A is synthesized in skin 
d. All vitamin A derivatives are safe to use during pregnancy 
e. Vitamin A is a form of calciferol 
 
27. Which of the following statements describing vitamin K is true? 
a. VitaminK is broken down by intestinal bacteria 
b. Vitamin K is obtained by eating citrus fruits, spinach, and cabbage 
c. Vitamin K is not found in dairy or meat products; it is obtained by eating egg 
yolk and liver 
d. Vitamin K is required for liver synthesis of prothrombin 
e. Vitamin K prevents thrombosis 
 
28. Which one of the following is a cofactor and not a coenzyme? 
a. Biotin 
b. Tetrahydrofolic acid 
c. Copper 
d. Methylcobalamin 
e. Pyridoxal phosphate 
 
 
 
29. Which of the following is a coenzyme? 
a. Glucose-6-phosphate 
b. Glucose-1-phosphate 
c. Calcium ion 
d. Lipoic acid 
e. UDP-glucose 
 
30. Which one of the following cofactors must be utilized during the conversion of acetyl CoA 
to malonyl CoA? 
a. Thiamine pyrophosphate 
b. Acyl carrier protein (ACP) 
c. NAD1 
d. Biotin 
e. FAD 
 
31. Which one of the following transfers acyl groups? 
a. Thiamine pyrophosphate 
b. Lipoamide 
c. ATP 
d. NADH 
e. FADH 
 
32. Both acyl carrier protein (ACP) of fatty acid synthetase and coenzyme A (CoA) 
a. Contain reactive phosphorylated tyrosine groups 
b. Contain thymidine 
c. Contain phosphopantetheine-reactive groups 
d. Contain cystine-reactive groups 
e. Carry folate groups 
 
33. Which of the following vitamins is the precursor of CoA? 
a. Riboflavin 
b. Pantothenate 
c. Thiamine 
d. Cobamide 
e. Pyridoxamine 
 
34. Biotin is involved in which of the following types of reactions? 
a. Hydroxylations 
b. Carboxylations 
c. Decarboxylations 
d. Dehydrations 
e. Deaminations 
 
 
 
 
 
35. Studies of the actions of two anticoagulants—dicumarol and warfarin 
(the latter also a hemorrhagic rat poison)—have revealed that 
a. Vitamin C is necessary for the synthesis of fibrinogen 
b. Vitamin C activates fibrinogen 
c. Vitamin K is a clotting factor 
d. Vitamin K is essential for γ-carboxylation of glutamate 
e. The action of vitamin E is antagonized by these compounds 
 
36. Pantothenic acid is a constituent of the coenzyme involved in 
a. Decarboxylation 
b. Acetylation 
c. Dehydrogenation 
d. Reduction 
e. Oxidation 
 
37. Fully activated pyruvate carboxylase depends upon the presence of 
a. Malate and niacin 
b. Acetyl CoA and biotin 
c. Acetyl CoA and thiamine pyrophosphate 
d. Oxaloacetate and biotin 
e. Oxaloacetate and niacin 
 
38. Which of the following statements regarding vitamin A is true? 
a. It is not an essential vitamin 
b. It is related to tocopherol 
c. It is a component of rhodopsin 
d. It is derived from ethanol 
e. It is also known as opsin 
 
39. Which of the following vitamins would most likely become deficient in a person who 
develops a completely carnivorous lifestyle? 
a. Thiamine 
b. Niacin 
c. Cobalamin 
d. Pantothenic acid 
e. Vitamin C 
 
40. Humans most easily tolerate a lack of which of the following nutrients? 
a. Protein 
b. Iodine 
c. Carbohydrate 
d. Lipid 
e. Calcium 
 
 
 
 
41. Which of the activated groups or units is most closely associated with uridine diphosphate 
(UDP)? 
a. Electrons 
b. Phosphoryl 
c. Acyl 
d. Aldehyde 
e. Glucose 
 
42. Which of the following compounds is an analogue of hypoxanthine? 
a. Ara C 
b. Allopurinol 
c. Ribose phosphate 
d. 5-phosphoribosylpyrophosphate (PRPP) 
e. 5-FU 
 
43. Which statement best describes xanthine? 
a. It is a direct precursor of guanine 
b. It covalently binds to allopurinol 
c. It is a substrate rather than a product of the enzyme xanthine oxidase 
d. It is oxidized to form uric acid 
e. It is oxidized to form hypoxanthine 
 
44. When the liver is actively synthesizing fatty acids, a concomitant decrease in β oxidation of 
fatty acids is due to: 
a. Inhibition of a translocation between cellular compartments 
b. Inhibition by an end product 
c. Activation of an enzyme 
d. Detergent effects 
e. Decreases in adipocyte lipolysis 
 
45. The synthesis of 3-hydroxy-3-methylglutaryl CoA can occur: 
a. Only in mitochondria of all mammalian tissues 
b. Only in the cytosol of all mammalian tissues 
c. Only in the endoplasmic reticulum of all mammalian tissues 
d. In both the cytosol and mitochondria 
e. In lysosomes 
 
46. Which of the following is not used in the synthesis of fatty acids? 
a. Cobalamin (vitamin B12) 
b. NADPH 
c. AMP 
d. FADH2 
e. HCO3 
 
 
 
 
47. For every 2 mol of free glycerol released by lipolysis of triacylglycerides in adipose tissue: 
a. 2 mol of triacylglycerides is released 
b. 2 mol of free fatty acids is released 
c. 1 mol of glucose can be synthesized in gluconeogenesis 
d. 1 mol of triacylglyceride is released 
e. 3 mol of acyl CoA is produced 
 
48. During fatty acid metabolism in humans, coenzyme A (CoA) is different from acyl carrier 
protein (ACP) in which one of the following ways? 
a. Binding of malonic acid with a phosphopantetheine 
b. Binding of fatty acids 
c. Function in fatty acid oxidation 
d. Function in the cytosol 
e. Function in fatty acid synthesis 
 
49. Most of the reducing equivalents utilized for synthesis of fatty acids can be generated from: 
a. The pentose phosphate pathway 
b. Glycolysis 
c. The citric acid cycle 
d. Mitochondrial malate dehydrogenase 
e. Citrate lyase 
 
50. Which of the following lipoproteins would contribute to a measurement of plasma 
cholesterol in a normal person following a 12-h fast? 
a. Very-low-density lipoproteins 
b. High-density lipoproteins 
c. Chylomicrons 
d. Chylomicron remnants 
e. Adipocyte lipid droplets 
 
 
51. Which one of the following apolipoproteins is synthesized in the liver as part of the coat of 
very-low-density lipoproteins (VLDLs)? 
a. AI 
b. B48 
c. CII 
d. B100 
e. E 
 
52. The fatty acid synthase complex of mammals: 
a. Is a dimer of unsimilar subunits 
b. Is composed of seven different proteins 
c. Dissociates into eight different proteins 
d. Catalyzes eight different enzymatic steps 
e. Is composed of covalently linked enzymes 
 
 
53. The end product of cytosol fatty acid synthetase in humans is: 
a. Oleic acid 
b. Arachidonic acid 
c. Linoleic acid 
d. Palmitic acid 
e. Palmitoleic acid 
 
54. Which of the following is most characteristic of a sphingolipidosis? 
a. Multifactorial inheritance 
b. Variable activities of abnormal enzyme in different patient tissues 
c. Deficiency of a hydrolytic enzyme 
d. Abnormalities of sphingolipid synthesis 
e. Accumulation of ceramide-containing lipids 
 
55. Which of the following steps in the biosynthesis of cholesterol is thought to be rate-
controlling and the locus of metabolic regulation? 
a. Geranyl pyrophosphate → farnesyl pyrophosphate 
b. Squalene → lanosterol 
c. Lanosterol → cholesterol 
d. 3-hydroxy-3-methylglutaryl CoA → mevalonic acid 
e. Mevalonic acid → geranyl pyrophosphate 
 
56. Ceramide is a precursor to which of the following compounds? 
a. Phosphatidyl serine 
b. Sphingomyelin 
c. Phosphatidyl glycerol 
d. Phosphatidyl choline 
e. Phosphatidyl ethanolamine 
 
57. Chylomicrons, intermediate-density lipoproteins (IDLs), low-density lipoproteins (LDLs), and 
very-low-density lipoproteins (VLDLs) are all serum lipoproteins. What is the correct 
ordering of these particles from the lowest to the highest density? 
a. LDLs, IDLs, VLDLs, chylomicrons 
b. Chylomicrons, VLDLs, IDLs, LDLs 
c. VLDLs, IDLs, LDLs, chylomicrons 
d. Chylomicrons, IDLs, VLDLs, LDLs 
e. LDLs, VLDLs, IDLs, chylomicrons 
 
58. Which of the followingamino acids is a precursor to cysteine? 
a. Threonine 
b. Methionine 
c. Glutamine 
d. Lysine 
e. Alanine 
 
 
 
59. Which of the metabolites below is a precursor of tyrosine? 
a. L-dihydroxyphenylalanine (dopa) 
b. Dopamine 
c. Norepinephrine 
d. Epinephrine 
e. Phenylalanine 
 
60. The reactions of the urea cycle occur 
a. In the cytosol 
b. In the mitochondrial matrix 
c. In the mitochondrial matrix and the cytosol 
d. Only in lysosomes 
e. In peroxisomes 
 
61. Which one of the following tissues can metabolize glucose, fatty 
acids, and ketone bodies for ATP production? 
a. Liver 
b. Muscle 
c. Hepatocytes 
d. Brain 
e. Red blood cells 
 
62. The problem of regenerating NAD+ from NADH for cytoplasmic processes by using 
mitochondria is solved in the most energy-efficient manner by which one of the following 
intercellular shuttle systems? 
a. Citrate → pyruvate shuttle 
b. Dihydroxyacetone phosphate →α-glycerophosphate shuttle 
c. Malate → aspartate shuttle 
d. Citrate → citrate shuttle 
e. Lactate → pyruvate shuttle 
 
63. Which of the descriptions below best fits inositol 1,4,5-triphosphate? 
a. A depositor of calcium in endoplasmic reticulum 
b. An inhibitor of protein kinase C 
c. A second messenger produced by the action of phospholipase C 
d. An ionophore 
e. A calcium detector 
 
64. Which enzyme is an allosteric regulator of another enzyme on the list? 
a. Acetyl coenzyme A carboxylase 
b. Pancreatic lipase 
c. Carnitine acyltransferase I 
d. Diacylglycerol lipase 
e. Hormone-sensitive lipase 
 
 
 
65. Which of the following correctly describes the intermediate 3-hydroxy-3-methylglutaryl 
CoA? 
a. It inhibits the conversion of cholesterol to sex steroids 
b. It is formed only in the cytoplasm 
c. It inhibits the first step in cholesterol synthesis 
d. It is formed by condensation of two molecules of acetyl CoA 
e. It is an intermediate in the synthesis of cholesterol 
 
66. Which of the following statements about mammalian energy metabolism is true? 
a. ATP is only formed in the absence of Q2 
b. ATP hydrolysis is an exergonic reaction 
c. ATP is only formed in the presence of Q2 
d. Heat produced by ATP hydrolysis specifically drives other reactions 
e. NADH cannot be utilized to form ATP 
 
67. Inhibition of the synthesis of ATP during oxidative phosphorylation by oligomycin is thought 
to be due to: 
a. Blocking of the proton gradient between NADH-Q reductase and QH2 
b. Blocking of the proton gradient between cytochrome c1 and cytochrome c 
c. Dissociating of cytochrome c from mitochondrial membranes 
d. Inhibiting of mitochondrial ATPase (ATP synthase) 
e. Uncoupling of electron transfer between NADH and flavoprotein 
 
68. Which of the following regulates lipolysis in adipocytes? 
a. Activation of fatty acid synthesis mediated by cyclic AMP 
b. Activation of triglyceride lipase as a result of hormone-stimulated increases in 
cyclic AMP levels 
c. Glycerol phosphorylation to prevent futile esterification of fatty acids 
d. Activation of cyclic AMP production by insulin 
e. Hormone-sensitive lipoprotein lipase 
 
69. Which one of the following products of triacylglycerol breakdown and subsequent β 
oxidation may undergo gluconeogenesis? 
a. Propionyl CoA 
b. Acetyl CoA 
c. All ketone bodies 
d. Some amino acids 
e. β-hydroxybutyrate 
 
70. Which one of the following enzymes catalyzes high-energy phosphorylation of substrates 
during glycolysis? 
a. Pyruvate kinase 
b. Phosphoglycerate kinase 
c. Triose phosphate isomerase 
d. Aldolase 
e. Glyceraldehyde-3-phosphate dehydrogenase 
 
71. Which of the following reactions generates ATP? 
a. Glucose-6-phosphate to fructose-6-phosphate 
b. Glucose to glucose-6-phosphate 
c. Fructose-6-phosphate to fructose-1,6-diphosphate 
d. Phosphoenolpyruvate to pyruvate 
e. Pyruvate to lactate 
 
72. Which of the following steps is involved in the generation of glucose from lipolysis? 
a. Glycerol from lipolysis is converted to triglycerides 
b. Fatty acids from lipolysis are oxidized, producing NADH and stimulating gluconeogenesis 
c. Glycerol from lipolysis is phosphorylated, converted to fructose-1,6- 
bisphosphate, and eventually converted to glucose 
d. Fatty acids from lipolysis stimulate the citric acid cycle 
e. Glycerol from lipolysis is taken up by liver cells and dimerized to fructose 
 
73. After a meal, blood glucose enters cells and is stored as glycogen, particularly in the liver. 
Which of the following is the donor of new glucose molecules in glycogen? 
a. UDP-glucose-1-phosphate 
b. UDP-glucose 
c. UDP-glucose-6-phosphate 
d. glucose-6-phosphate 
e. glucose-1-phosphate 
 
74. A man goes on a hunger strike and confines himself to a liquid diet with minimal calories. 
Which of the following would occur after 4 to 5 h? 
a. Decreased cyclic AMP and increased liver glycogen synthesis 
b. Increased cyclic AMP and increased liver glycogenolysis 
c. Decreased epinephrine levels and increased liver glycogenolysis 
d. Increased Ca++ in muscle and decreased glycogenolysis 
e. Decreased Ca++ in muscle and decreased glycogenolysis 
 
75. Which of the following statements about glycogen metabolism is true? 
a. Cyclic AMP–activated protein kinase stimulates glycogen synthase 
b. Phosphorylase kinase is activated by phosphorylation 
c. Phosphorylase b is inactivated by phosphorylation 
d. Cyclic AMP levels are lowered by epinephrine and glucagon stimulation of 
adenylate cyclase 
e. Glycogen synthesis is stimulated by glucagon 
 
76. In the pathway leading to biosynthesis of acetoacetate from acetyl CoA in the liver, the 
immediate precursor of acetoacetate is which of the following substances? 
a. 3-hydroxybutyrate 
b. Acetoacetyl CoA 
c. 3-hydroxybutyryl CoA 
d. Mevalonic acid 
e. 3-hydroxy-3-methylglutaryl CoA 
 
77. Which of the following statements correctly describes ketone bodies? (está feita de outra 
maneira) 
a. They accumulate in children with fatty acid oxidation disorders 
b. They accumulate in diabetes mellitus after insulin therapy 
c. They are produced by muscle but not by liver 
d. They include β-hydroxybutyrate and acetone 
e. They are found in blood but not in urine 
 
78. The entry point into the citric acid cycle for isoleucine, valine, and the product of odd-chain 
fatty acids is: 
a. Fumarate 
b. Pyruvate 
c. Oxaloacetate 
d. Citrate 
e. Succinyl CoA 
 
79. Reduction of which one of the following substrates leads to a reducing equivalent in a step 
of the citric acid cycle? 
a. Succinyl CoA 
b. Malate 
c. Fumarate 
d. Oxaloacetate 
e. Citrate 
 
80. Citrate has a positive allosteric effect on which one of the following enzymes? 
a. Pyruvate kinase 
b. Acetyl CoA carboxylase 
c. Phosphofructokinase 
d. Fatty acid synthetase 
e. Enolase 
 
81. After alcohol ingestion, which of the following intermediates accumulates in liver that is not 
typical of glycolysis or the citric acid cycle? 
a. Acetyl CoA 
b. Lactate 
c. Acetaldehyde 
d. Citrate 
e. Oxaloacetate 
Carbohydrate Metabolism 149 
 
82. Which of the following events occurs during formation of phosphoenolpyruvate from 
pyruvate during gluconeogenesis? 
a. CO2 is consumed 
b. Inorganic phosphate is consumed 
c. Acetyl CoA is utilized 
d. ATP is generated 
e. GTP is generated 
 
83. Which one of the following activities is simultaneously stimulated by epinephrine in muscle 
and inhibited by epinephrine in the liver? 
a. Fatty acid oxidation 
b. Glycogenolysisc. Cyclic AMP synthesis 
d. Glycolysis 
e. Activation of phosphorylase 
 
84. Glycogen synthetase, the enzyme involved in the biosynthesis of glycogen, may: 
a. Be activated by the phosphorylation of a specific serine residue 
b. Be activated by increased calcium levels 
c. Be more specifically defined as UDP-glucose-glycogen glucosyl transferase 
d. Synthesize glycogen without a polymer primer 
e. Employ UDP-D-glucose as a glucosyl donor in both plants and animals 
 
85. The activity of pyruvate carboxylase is dependent upon the positive allosteric effector: 
a. Succinate 
b. AMP 
c. Isocitrate 
d. Citrate 
e. Acetyl CoA 
 
86. Which of the following hormones stimulates gluconeogenesis? 
a. Progesterone 
b. Glucagon 
c. Aldosterone 
d. Epinephrine 
e. Thyroxine 
f. Growth hormone 
g. Insulin 
h. Glucocorticoids 
 
87. Which of the following is an allosteric effector that enhances activity of 
phosphofructokinase of the glycolytic pathway? 
a. Adenosine monophosphate (AMP) 
b. Citric acid 
c. Adenosine triphosphate (ATP) 
d. Glucose-6-phosphate 
e. Glucose 
 
88. Which of the following metabolites is involved in glycogenolysis, glycolysis, and 
gluconeogenesis? 
a. Galactose-1-phosphate 
b. Glucose-6-phosphate 
c. Uridine diphosphoglucose 
d. Fructose-6-phosphate 
e. Uridine diphosphogalactose 
 
89. After a well-rounded breakfast, which of the following would be expected to occur? 
a. Increased activity of pyruvate carboxylase 
b. Decreased activity of acetyl CoA carboxylase 
c. Decreased rate of glycogenolysis 
d. Decreased rate of protein synthesis 
e. Increased activity of phosphoenolpyruvate carboxykinase 
 
90. Which one of the following enzymes catalyzes phosphorylation with the use of inorganic 
phosphate? 
a. Hexokinase 
b. Phosphofructokinase 
c. Glyceraldehyde-3-phosphate dehydrogenase 
d. Phosphoglycerate kinase 
e. Pyruvate kinase 
 
91. Which one of the following enzymes is common to both glycolysis and gluconeogenesis? 
a. Pyruvate kinase 
b. Pyruvate carboxylase 
c. Hexokinase 
d. Phosphoglycerate kinase 
e. Fructose-1,6-bisphosphatase 
 
92. Which one of the following enzymes catalyzes high-energy phosphorylation of substrates 
during glycolysis? 
a. Pyruvate kinase 
b. Phosphoglycerate kinase 
c. Triose phosphate isomerase 
d. Aldolase 
e. Glyceraldehyde-3-phosphate dehydrogenase 
 
93. Which of the amino acids below is the uncharged derivative of an acidic amino acid? 
a. Cystine 
b. Arginine 
c. Tyrosine 
d. Glutamine 
e. Proline 
f. Serine 
g. Leucine 
 
94. Under normal conditions in blood, which of the following amino acid residues of albumin is 
neutral? 
a. Arginine 
b. Aspartate 
c. Glutamine 
d. Glutamate 
e. Histidine 
 
95. Which one of the following proteolytic enzymes is activated by acid hydrolysis of the 
proenzyme form? 
a. Trypsin 
b. Chymotrypsin 
c. Elastase 
d. Pepsin 
e. Carboxypeptidase