1. Chymotrypsin is a proteolytic enzyme acting in the digestive systems of many organisms. Which amino acid is NOT contained in the catalytic triad in
chymotrypsin?
A. Lys B. Ser C. His D. Asp
2. Which attribute of biological membrane is NOT correct?
A. Membranes consist mainly of lipids and proteins.
B. The constituent protein and lipid molecules are held together by covalent bond
in the membrane.
C. Membranes are asymmetric. D. Membranes are fluid structures.
3. Which molecule below is the key regulator of membrane fluidity in animals?
A. Glycolipids B. Fatty acid C. Integral membrane proteins D. Cholesterol
4. Which description is NOT correct?
A. A nucleic acid consists of four kinds of bases linked to a sugar–phosphate
backbone.
B. A pair of nucleic acid strands with complementary sequences can form a
double-helical structure.
C. DNA is a structurally rigid molecule that only exist in a specific helical form. D. Double-stranded DNA can wrap around itself to form a supercoiled structure.
5. Which of the following force does NOT exist in the quaternary structure of the protein?
A. Electrostatic interaction B. Van der Waals force C. H-bonds D. Disulfide bond
6. What kind of protein secondary structure is silk (fibroin) made of?
A. α-helix B. β-sheet C. β-turns D. Random coils
7. What type of inhibitor does penicillin belong to?
A. Competitive inhibition B. Uncompetitive inhibition C. Noncompetitive inhibition D. Irreversible inhibitors
9. Which of the following is least likely to cross a cellular membrane without transporters or channels?
A. Inorganic ions B. Larger uncharged polar molecules
C. Small uncharged polar molecules D. Small nonpolar molecules
10. Which description is NOT correct?
A. Cyclic AMP stimulates the phosphorylation of many target proteins by
activating protein kinase A.
B. Natrium ion is a widely used second messenger.
C. Activated G proteins transmit signals by binding to other proteins. D. G proteins spontaneously reset themselves through GTP hydrolysis.
11. Which description is NOT correct?
A. The insulin receptor is a dimer that closes around a bound insulin molecule. B. Insulin binding results activation of the insulin receptor.
C. The activated insulin-receptor kinase initiates a kinase cascade. D. Insulin signaling is terminated by the action of methyltransferases.
12. What is a prion which cause mad cow disease?
A. Misfolded DNA B. Misfolded RNA C. Misfolded protein D. Misfolded polysaccharide
13. Which of the following is NOT high energy molecule in cellular respiration?
A. ATP B. AMP C. NADH D. FADH2
14. Which of the following is NOT a second messenger molecule?
A. Estrogen B. Inositol 1,4,5-trisphosphate (IP3) C. Diacylglycerol (DAG)
D. Cyclic AMP
15. The binding of signaling molecules to their receptors initiates pathways that lead to important physiological responses. Which receptor of signal-transduction pathways is involved in glucose uptake regulation?
A. Sialic acid receptor B. β-Adrenergic receptor C. Insulin receptor D. EGF receptor
16. Which description is NOT correct?
A. The insulin receptor is a dimer that closes around a bound insulin molecule. B. Insulin binding results activation of the insulin receptor.
C. The activated insulin-receptor kinase initiates a kinase cascade. D. Insulin signaling is terminated by the action of methyltransferases.
17. Which description is NOT correct?
A. Actin is a polar, self-assembling, dynamic polymer. B. Myosin motion along actin.
C. Actin motion along myosin.
D. Phosphate release triggers the myosin power stroke.
18. Microtubules are key components of cilia and flagella present on some eukaryotic cells. What is the structural type of the microtubules (called an axoneme)?
A. 8+1 array B. 9+1 array C. 8+2 array D. 9+2 array
19. What is the major electron donor in reductive biosynthesis reactions?
A. ATP B. NADH C. NADPH D. FADH2
20. What is the universal currency of free energy in biological system?
A. ATP B. NADH C. NADPH D. FADH2
21. Which bases of DNA can be methylated?
A. Adenine and Cytosine B. Adenine and thymine C. Guanine and thymine D. Guanine and Cytosine
22. Oseltamivir (Tamiflu) is an antiviral medication used to treat influenza. Which of the following molecule is this neuraminidase inhibitor mimicking?
A. Matrix-2 (M2) protein B. Hemagglutinin (HA) C. Endonuclease D. Sialic acid
23. What is the net gain of ATP molecules production in the glycolysis?
A. 30 B. 8 C. 4 D. 2
25. What is the main place for the tricarboxylic acid (TCA) cycle in cells?
A. Cytosol B. Mitochondria C. Endoplasmic reticulum D. Peroxisome
26. Which complex in the respiratory chain is NOT a proton pump?
A. Complex I B. Complex II C. Complex III D. Complex VI
27. What complex can be inhibited by Rotenone and Amytal?
A. Complex I B. Complex II C. Complex III D. Complex VI
28. How many ATPs are spent synthesizing glucose from pyruvate in gluconeogenesis?
A. 2 B. 4 C. 6 D. 8
29. Which of the following level of molecule can regulate the rate of pentose phosphate pathway (PPP)?
A. ATP B. ADP C. NAD+ D. NADP+
30. Which of the following hormone can regulate the metabolism of glycogen?
A. Insulin B. Epinephrine C. Glucagon D. All of the above
31. Which of the following molecule is NOT generated in fatty acid oxidation?
A. NADPH B. NADH C. Acetyl CoA D. FADH2
32. Which description is NOT correct?
A. The complete oxidation of palmitate (CH3(CH2)14COOH) yields 106 molecules
of ATP.
B. Animals can convert fatty acids into glucose directly. C. Fatty acids are synthesized in the cytoplasm.
D. Intermediates in fatty acid synthesis are covalently linked to the sulfhydryl
groups of an acyl carrier protein (ACP).
33. Which of the following receptor plays a key role in controlling cholesterol metabolism?
34. Which of the following hormone is NOT derived from cholesterol?
A. Insulin B. Progesterone C. Androgens D. Estrogens
35. Which description of cytochrome P450 is correct?
A. Steroids are hydroxylated by cytochrome P450 monooxygenases that use
NADPH and O2.
B. The cytochrome P450 system, which in mammals is located primarily in the
smooth endoplasmic reticulum of the liver and small intestine.
C. The cytochrome P450 system metabolize ethanol. D. All of the above.
36. Which of the following compound is NOT involved in urea cycle?
A. Glutamate B. Ornithine C. Fumarate D. Aspartate
37. Which of the following coenzyme is required for aminotransferase?
A. Folic acid B. Biotin C. Flavin adenine dinucleotide D. Pyridoxal phosphate
38. Which of the following coenzyme is required for DNA synthesis?
A. Folic acid B. Biotin C. Flavin adenine dinucleotide D. Pyridoxal phosphate
39. Which description of ubiquitin is NOT correct?
A. Ubiquitin is highly conserved in eukaryotes and prokaryotes.
B. Ubiquitin attached to the -amino groups of several lysine residues on a protein
destined to be degraded.
C. The energy for the isopeptide bonds of ubiquitination comes from ATP
hydrolysis.
D. Three enzymes (E1, E2 and E3) participate in the attachment of ubiquitin to a
protein.
40. Which description of CRISPR/Cas9 is correct?
A. CRISPR/Cas9 is a novel protein metabolic pathway. B. CRISPR/Cas9 is a novel coenzyme.
41. Mitochondria are the primary sources of energy for cells, organs, and the living animal. Which enzyme is NOT contained in this organelle?
A. Succinate dehydrogenase B. Fumarase C. Cytochrome oxidase D. Rubisco
42. Which of the following ion plays a key role in extracting electrons from H2O to
form O2 in photosystem II of photosynthesis? A. Calcium B. Natrium C. Manganese D. Iron
43. Metabolism produces both inorganic and organic acids. Which metabolism produce(s) are nonvolatile and excreting via the kidney?
A. Lactic acid B. Acetoacetic acid C. β-hydroxybutyrate D. All of the above
44. Which of the following aqueous solutions has the lowest pH? The solutions have H+ concentration respectively of
A. 1.2 10-4 mol/L B. 2.3 10-3 mol/L C. 3.1 10-10 mol/L D. 4.5×10-6 mol/L
45. Acetic acid (CH3COOH) has a pKa of 4.76. What is the molar ratio of potassium
acetate (CH3COOK) to acetic acid at pH 4.76? A. 1:1 B. 2:1 C. 10:1 D. 1:10
46. Which amino acids are relatively nonpolar (hydrophobic)?
A. Phe, Tyr, Trp B. Ser, Asn, Gln C. Lys, Arg D. Asp, Glu
47. Which amino acids have positive charge at pH 7.0?
A. Phe, Tyr, Trp B. Ser, Asn, Gln C. Lys, Arg D. Asp, Glu
48. N-linked glycosylation is important process for both the structure and function of some eukaryotic proteins. Which amino acid plays a key role in this process? (N-glycans are attached to the nitrogen atom of this amino acid)
A. Pro B. Trp C. Lys D. Asn
49. Which amino acid has a significant effect on the tertiary structure of the protein?
A. Pro B. Trp C. Lys D. Asn
50. The indole group absorbs UV light at 280 nm. It is useful for spectrophotometric measurement of protein concentration. Which amino acid has an indole ring?
51. Which amino acids carry a negative charge at pH 7.0?
A. Arg, Lys B. Phe, Try, Trp C. Glu, Asp D. None of the above
52. Which of the following pairs bonds can rotate within a peptide backbone and the torsion angle of the latter assigned as phi angle?
A. N-C and C-CO B. C-CO and N-C C. CO-N and N-C D. N-C and CO-N
53. Which one is NOT a component of inner mitochondrial membrane?
A. Cytochrome c B. NADH dehydrogenase C. Phosphatidylcholine D. Deoxyribonucleic acid
54. During the separation of protein molecules, which method relates to the isoelectric point (pI) of the protein?
A. Immunoprecipitation B. SDS-PAGE C. Ion exchange D. Gel filtration
55. During the separation of protein molecules, which method is related to protein denaturation?
A. Immunoprecipitation B. SDS-PAGE C. Ion exchange D. Gel filtration
56. Which nucleosides below contain both pyrimidines?
A. A, T B. C, T, U C. C, G D. A, G, U
57. What force drives the formation of protein tertiary structure?
A. Van der Waals force B. Electrostatic interaction C. H-bonds D. All of the above
58. When a polymer of 36-residue forms an α-helix, how many repeats would you expect it to be?
A. 7 B. 8 C. 9 D. 10
59. What type of inhibitor X is this Lineweaver–Burk plot shown?
1/V
1/VMax
60. What type of inhibitor Y is this Lineweaver–Burk plot shown? 1/[S] 1/V 1/VMax 1/Km Inhibitor Y
A. Competitive inhibition B. Uncompetitive inhibition C. Noncompetitive inhibition D. Irreversible inhibitors
61. Which description is NOT correct?
A. Allosteric interactions in Aspartate transcarbamoylase (ATCase) are mediated
by large changes in quaternary structure.
B. Chymotrypsinogen is activated by specific cleavage of a single peptide bond. C. Blood clotting is accomplished by a single-step zymogen activation.
D. Phosphorylation is a highly effective means of regulating the activities of target
proteins.
62. Which description is NOT correct?
A. Water-soluble proteins fold into compact structures with polar cores. B. The water-soluble proteins have an interior formed of amino acids with
hydrophobic side chains.
C. The water-soluble proteins have a surface formed largely of hydrophilic amino
acids.
D. The hydrophobic interactions between the interior residues are the driving force
for the formation of the tertiary structure of water-soluble proteins. 63. Which one is NOT a component of ribonucleic acid?
A. Adenine B. Guanine C. Thymine D. Cytosine
64. Which step of polymerase chain reaction (PCR) cycle requires the highest temperature?
A. Denaturation B. Annealing C. Elongation D. Hybridization
65. Which step of polymerase chain reaction (PCR) cycle requires a heat-stable DNA polymerase?
66. Which of the following immunoglobulin has the largest molecular weight?
A. IgG B. IgA C. IgM D. IgY
67. What kind of immunoglobulin does NOT exist in humans?
A. IgG B. IgA C. IgM D. IgY
68. Which kind of cells are involved in monoclonal antibody production?
A. Epithelial Cells B. Endothelial cells C. Cardiomyocyte Cells D. Hybridoma cells
69. Which method can determine the amino acid sequence from a protein?
A. Edman degradation B. Polymerase chain reaction C. Ultracentrifugation D. X-ray crystallography
70. Which method can determine the three-dimensional structure from a protein?
A. Edman degradation B. Polymerase chain reaction C. Ultracentrifugation D. X-ray crystallography
71. Which kind of molecule is NOT included in the central dogma of molecular biology?
A. Phospholipid B. Deoxyribonucleic acid C. Ribonucleic acid D. Protein
72. Which kind of mechanism is included in the central dogma of molecular biology?
A. Replication B. Transcription C. Translation D. All of the above
73. Which codon is NOT stop signals for protein synthesis?
A. UAA B. UAG C. UGA D. AUG
74. Which one is NOT key tools in forming recombinant DNA molecules?
A. DNA topoisomerases B. Restriction enzyme C. DNA ligase D. Plasmid
75. Which molecule below is most likely to form a base-paired hairpin structure?
77. Which of the following molecule is the most important substrate for hexokinase?
A. ADP B. ATP C. Glucose D. Mannose
78. What enzyme catalyzes the relaxation of supercoiled DNA?
A. Telomerase B. Helicase C. Ligase D. Topoisomerase
79. What enzyme catalyzes to separate strands of a DNA double helix?
A. Telomerase B. Helicase C. Ligase D. Topoisomerase
80. Which of the following sequence is NOT contained in the promoter of the eukaryotes?
