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Question 1 A reaction with a delta G of zero:
a. Requires energy
b. Is at equilibrium
c. Is spontaneous
d. None of the above
Question 2 A solution with a pH of 5 is:
a. Acidic
b. Basic
c. Neutral
d. None of the above
Question 3 Alcohols contain a _________ group.
a. Hydroxyl
b. Sulfur
c. Phenol
d. None of the above
Question 4 Biologically important noncovalent bonds include:
a. Van der Waals interactions
b. Hydrogen bonds
c. Electrostatic interactions
d. All of the above
Question 5 Entropy is ______________.
a. The degree of disorder of a system
b. The degree of energy of a system
c. A type of noncovalent bond
d. A type of covalent bond
Question 6 The DNA of a eukaryotic cell is stored within the _____________.
a. Lysosome
b. Nucleus
c. Ribosome
d. Endoplasmic Reticulum
Question 7 The term "kinetics" refers to:
a. The energy required for a reaction
b. The disorder of a system
c. The speed at which a reaction will occur
d. The pH of a solution
Question 8 ______ is the process by which the information in DNA is transferred to RNA.
a. Translation
b. Replication
c. Transcription
d. Ubiquitination
Question 9 The strongest bonds that are present in biochemical compounds are ______________.
a. Ionic bonds
b. Covalent bonds
c. Hydrogen bonds
d. Van der Waals interactions
Question 10 A chiral compound _________________.
a. Is non-superimposable on its mirror image
b. Is the same as its mirror image
c. Is inorganic
d. Contains a sulfur atom
Question 11 A zwitterion ________________.
a. Has a positive charge
b. Has a negative charge
c. Overall, has no charge
d. All of the above
Question 12 All amino acids contain both a(n) ______ and a(n) ________ group.
a. Hydrogen, carbohydrate
b. Amine, carboxylic acid
c. Sulfur, amine
d. None of the above
Question 13 Essential amino acids:
a. Are made by organisms
b. Must be obtained from dietary sources
c. Are made from DNA
d. Include proline
Question 14 The first reaction of amino acid degradation is?
a. Deamination
b. Decarboxylation
c. Cyclization
d. None of the above
Question 15 The only amino acid without a chiral center is _____________.
a. Proline
b. Methionine
c. Alanine
d. Glycine
Question 16 There are ______ common amino acids.
a. 15
b. 25
c. 20
d. 10
Question 17 ______ is the initiating amino acid of most newly synthesized proteins.
a. Proline
b. Alanine
c. Glycine
d. Methionine
Question 18 _____________ is an example of a hydrophilic amino acid.
a. Lysine
b. Leucine
c. Methionine
d. Tryptophan
Question 19 _____________ is an example of a hydrophobic amino acid.
a. Glutamic acid
b. Lysine
c. Arginine
d. Leucine
Question 20 Nonessential amino acids are:
a. Provided in the diet
b. Synthesized by mammals
c. Both A and B
d. None of the above
Question 21 A(n) _________ is a short protein tag that attaches to and targets proteins for degradation.
a. Peptide
b. Ubiquitin
c. Alanine
d. Urea
Question 22 Protein secondary structures include:
a. Loops
b. alpha helices
c. beta sheets
d. All of the above
Question 23 Protein synthesis is carried out by __________.
a. Mitochondria
b. Chromosomes
c. Ribosomes
d. Lysosomes
Question 24 The amino acid _______ places certain constraints on the protein backbone.
a. Leucine
b. Alanine
c. Proline
d. Glycine
Question 25 The difference between a peptide and a protein is ____________.
a. Length
b. Bond formation
c. Subunits
d. All of the above
Question 26 The formation of a dimer refers to a protein's ___________.
a. Primary structure
b. Tertiary structure
c. Secondary structure
d. None of the above
Question 27 The tertiary structure of a protein refers to its __________.
a. Overall 3D shape
b. Multisubunit composition
c. Amino acid sequence
d. None of the above
Question 28 The ______ carries out protein degradation.
a. Proteosome
b. Lysosome
c. Ribosome
d. Chromosome
Question 29 ________ aid in protein folding.
a. Chromosomes
b. Chaperones
c. Proteosome
d. None of the above
Question 30 Amino acids are linked by a(n) _______ bond to form a protein.
In animals, the process of gluconeogenesis occurs in the __________.
a. Fat
b. Liver
c. Spleen
d. Gall bladder
Question 45 Lectins are ____________.
a. DNA binding proteins
b. Lipid binding proteins
c. Carbohydrate binding proteins
d. None of the above
Question 46 Protein glycosylation takes place in the ____________.
a. Nucleus
b. Cell membrane
c. Golgi apparatus
d. Lysosome
Question 47 Starch is an example of a ___________.
a. Monosaccharide
b. Disaccharide
c. Polysaccharide
d. Trisaccharide
Question 48 Sucrose, aka table sugar, is composed of ____________.
a. Glucose
b. Fructose
c. Both A and B
d. Neither A or B
Question 49 Fischer projections convey useful information about _____________.
a. Electron positions
b. 3D structural positioning
c. Resonance
d. Bond lengths
Question 50 ATP facilitates the occurrence of energetically unfavorable reactions via ___________.
a. Phosphoryl transfer
b. Energy coupling
c. ATP to ADP conversion
d. All of the above
Question 51
Both DNA and RNA are composed of three important parts, which are:
a. Glucose, side chains, phosphate group
b. Nitrogenouse base, phosphate group, sugar
c. Nitrogenous base, peptide bond, lipid
d. Phosphate group, sugar, side chain
Question 52 Cytosine makes _______ with guanine when base paired in DNA.
a. Three hydrogen bonds
b. Two hydrogen bonds
c. Three peptide bonds
d. Three covalent bonds
Question 53 DNA is synthesized in a _____ direction.
a. 3' to 5'
b. 5' to 3'
c. Top to bottom
d. Left to right
Question 54 Double stranded DNA takes on a __________ structure.
a. Beta sheet
b. Looped
c. Double helix
d. A-form helix
Question 55 In the cell, _____ is used as energy currency.
a. UTP
b. Fat
c. ATP
d. AMP
Question 56 The correct pairing of bases in DNA is __________.
a. A-G; C-T
b. A-C; G-T
c. A-T; C-G
d. A-U; C-G
Question 57 The DNA chromosome of bacteria consists of ___________.
a. A circular double stranded DNA
b. A circular single stranded DNA
c. A linear double stranded DNA
d. A linear single stranded DNA
Question 58 What is the base that is used by RNA but not DNA?
a. Guanine
b. Uracil
c. Thymine
d. Cytosine
Question 59 What type of base is adenine?
a. Purine
b. Pyrimidine
c. Both A and B
d. Neither A and B
Question 60 The sugar used in RNA is ____________.
a. Deoxyribose
b. Dideoxyribose
c. Ribose
d. Glucose
Question 61 Fatty acids contain ________________.
a. A carboxyl group and hydrocarbon chain
b. A phosphate group and hydrocarbon chain
c. A sugar group and hydrocarbon chain
d. Only a hydrocarbon chain
Question 62 Glycerolphospholipids create a double layer lipid membrane, such as the cell membrane, because of _____________.
a. Their high energy phospho group
b. Their hydrophilic heads and hydrophobic tails
c. Their unsaturated tails
d. Their ability to covalently bond to each other
Question 63 Lipids are the starting material of important biological molecules, including ___________.
a. Steroids
b. DNA
c. Carbohydrates
d. All of the above
Question 64 Lipids play a role in which of the following?
a. Energy storage
b. Membrane structure
c. Cell signaling
d. All of the above
Question 65 Phospholipids can be composed of _______________.
a. Fatty acids
b. Glycerol
c. Sphingomyelin
d. All of the above
Question 66 The difference between saturated and unsaturated fatty acids is ______________.
a. The number of hydrocarbon chains
b. The length of the hydrocarbon chain
c. The presence of single or double bonds in the
hydrocarbon chain
d. All of the above
Question 67 The fluidity of the cell membrane is determined by ___________.
a. The lipid content
b. The amount of cholesterol present
c. The number of saturated and unsaturated fatty acids
present
d. All of the above
Question 68 Triacylglycerol is composed of ___________.
a. Glycerol and fatty acids
b. Glycerol and long chain alcohols
c. Glycerol and cholesterol
d. None of the above
Question 69 Which of the following are composed of lipids?
a. Waxes
b. Cholesterol
c. Triacylglecerols
d. All of the above
Question 70 Glycolysis gives a net yield of __________.
a. 8 moles ATP per glucose
b. 1 mole ATP per glucose
c. 2 moles ATP per glucose
d. 3 moles ATP per glucose
Question 71 Glycolysis takes place in the _________.
a. Cytosol
b. Mitochondria
c. Nucleus
d. Golgi
Question 72 In the citrate cycle, energy from the oxidation of acetyl-CoA is converted to _____________.
Question 87 There are three types of RNA polymerases in eukaryotic cells. RNA polymerase I transcribes ______, RNA polymerase II transcribes _______, and RNA polymerase III mainly transcribes _________.
a. Introns, mRNA, rRNA
b. rRNA, mRNA, tRNA
c. tRNA, introns, rRNA
d. mRNA, tRNA, rRNA
Question 88 Which of the following are post-transcriptional modifications of RNA?
a. Cap addition
b. Poly A tail addition
c. Intron removal
d. All of the above
Question 89 _________ enzymes maintain the torsional stress of DNA.
a. Helicase
b. Topoisomerase
c. Kinase
d. Restriction
Question 90 Activation of receptor tyrosine kinases results in ____________.
a. The opening of ion channels
b. The phosphorylation of the receptor
c. Membrane potential alterations
d. The exchange of GTP for GDP
Question 91 Intracellular pathways are altered through extracellular molecules binding to __________.
a. Polymerases
b. Ligases
c. Receptors
d. All of the above
Question 92 Molecules that play an important role in cell adhesion and structure include _________.
a. Integrins
b. Cadherins
c. Selectins
d. All of the above
Question 93 Steroids act as signaling molecules by __________________.
a. Binding to extracellular domains of receptor molecules
b. Binding to the plasma membrane
c. Binding to receptors internal to the cell
d. None of the above
Question 94 True or false: Ligand binding to receptors can result in wide- spread gene expression changes via signal amplification.
a. True
b. False
Question 95 Stimulation of a G protein coupled receptor results in __________.
a. The flow of ions through the receptor
b. Phosphorylation of the receptor
c. The exchange of GDP for GTP
d. None of the above
Question 96 ELISAs use __________, enabling the measurement of specific proteins in a solution.
a. PCR
b. Purification
c. Antibodies
d. None of the above
Question 97 In a Southern blot, probes are used to _________________.
a. Hybridize to a specific sequence of DNA
b. Hybridize to a specific sequence of RNA
c. Amplify a specific piece of DNA
d. Degrade a specific piece of RNA
Question 98 PCR is a valuable tool for analyzing DNA because ___________________.
a. It allows for the exponential amplification of a small
amount of starting material
b. It takes a short amount of time
c. The DNA sequence amplified need not be known
d. All of the above
Question 99 During SDS-PAGE, proteins are primarily separated according to their _______________.
a. Mass
b. Shape
c. Charge
d. All of the above
ANSWER KEY
1. B
2. A
3. A
4. D
5. A
6. B
7. C
8. C
9. B
10. A
11. D
12. B
13. B
14. A
15. D
16. C
17. D
18. A
19. D
20. C
21. B
22. D
23. C
24. C
25. A
26. D
27. A
28. A
29. B
30. B
31. B
32. D
33. B
34. A
35. C
36. D
37. B
38. D
39. D
40. B
41. D
42. A
43. C
44. B
45. C
46. C
47. C
48. C
49. B
50. D
51. B
52. A
53. B
54. C
55. C
56. C
57. A
58. B
59. A
60. C
61. A
62. B
63. A
64. D
65. D
66. C
67. D
68. A
69. D
70. C
71. A
72. B
73. C
74. D
75. C
76. B
77. D
78. A
79. B
80. B
81. A
82. A
83. C
84. B
85. B
86. D
87. B
88. D
89. B
90. B
91. C
92. D
93. C
94. A
95. C
96. C
97. A
98. D
99. A
