BIOCHEMISTRYÂ
51. All proteins contain the
(A) Same 20 amino acids
(B) Different amino acids
(C) 300 Amino acids occurring in nature
(D) Only a few amino acids
52. Proteins contain
(A) Only L- α – amino acids
(B) Only D-amino acids
(C) DL-Amino acids
(D) Both (A) and (B)
53. The optically inactive amino acid is
(A) Glycine
(B) Serine
(C) Threonine
(D) Valine
54. At neutral pH, a mixture of amino acids in solution would be predominantly:
(A) Dipolar ions
(B) Nonpolar molecules
(C) Positive and monovalent
(D) Hydrophobic
55. The true statement about solutions of amino acids at physiological pH is
(A) All amino acids contain both positive and negative charges
(B) All amino acids contain positivelyn charged side chains
(C) Some amino acids contain only positive charge
(D) All amino acids contain negatively charged side chains
56. pH (isoelectric pH) of alanine is
(A) 6.02
(B) 6.6
(C) 6.8
(D) 7.2
57. Since the pK values for aspartic acid are 2.0, 3.9 and 10.0, it follows that the isoelectric (pH) is
(A) 3.0
(B) 3.9
(C) 5.9
(D) 6.0
58. Sulphur containing amino acid is
(A) Methionine
(B) Leucine
(C) Valine
(D) Asparagine
59. An example of sulphur containing amino acid is
(A) 2-Amino-3-mercaptopropanoic acid
(B) 2-Amino-3-methylbutanoic acid
(C) 2-Amino-3-hydroxypropanoic acid
(D) Amino acetic acid
60. All the following are sulphur containing amino acids found in proteins except
(A) Cysteine
(B) Cystine
(C) Methionine
(D) Threonine
61. An aromatic amino acid is
(A) Lysine
(B) Tyrosine
(C) Taurine
(D) Arginine
62. The functions of plasma albumin are
(A) Osmosis
(B) Transport
(C) Immunity
(D) Both (A) and (B)
63. Amino acid with side chain containing basic groups is
(A) 2-Amino 5-guanidovaleric acid
(B) 2-Pyrrolidine carboxylic acid
(C) 2-Amino 3-mercaptopropanoic acid
(D) 2-Amino propanoic acid
64. An example of ααα-amino acid not present in proteins but essential in mammalian metabolism is
(A) 3-Amino 3-hydroxypropanoic acid
(B) 2-Amino 3-hydroxybutanoic acid
(C) 2-Amino 4-mercaptobutanoic acid
(D) 2-Amino 3-mercaptopropanoic acid
65. An essential amino acid in man is
(A) Aspartate
(B) Tyrosine
(C) Methionine
(D) Serine
66. Non-essential amino acids
(A) Are not components of tissue proteins
(B) May be synthesized in the body from essential amino acids
(C) Have no role in the metabolism
(D) May be synthesized in the body in diseased states
67. Which one of the following is semiessential amino acid for humans?
(A) Valine
(B) Arginine
(C) Lysine
(D) Tyrosine
68. An example of polar amino acid is
(A) Alanine
(B) Leucine
(C) Arginine
(D) Valine
69. The amino acid with a nonpolar side chain is
(A) Serine
(B) Valine
(C) Asparagine
(D) Threonine
70. A ketogenic amino acid is
(A) Valine
(B) Cysteine
(C) Leucine
(D) Threonine
71. An amino acid that does not form a ααα-helix is
(A) Valine
(B) Proline
(C) Tyrosine
(D) Tryptophan
72. An amino acid not found in proteins is
(A) β-Alanine                                                                                         (B) Proline
(C) Lysine                                                                                            (D) Histidine
73. In mammalian tissues serine can be a biosynthetic precursor of
(A) Methionine
(B) Glycine
(C) Tryptophan
(D) Phenylalanine
74. A vasodilating compound is produced by the decarboxylation of the amino acid:
(A) Arginine
(B) Aspartic acid
(C) Glutamine
(D) Histidine
75. Biuret reaction is specific for
(A) – CONH-linkages
(B) – CSNH2 group
(C) – (NH) NH2 group
(D) All of these
76. An example of a hydroxy fatty acid is
(A) Ricinoleic acid
(B) Crotonic acid
(C) Butyric acid
(D) Oleic acid
77. An example of a saturated fatty acid is
(A) Palmitic acid
(B) Oleic acid
(C) Linoleic acid
(D) Erucic acid
78. If the fatty acid is esterified with an alcohol of high molecular weight instead of glycerol, the resulting compound is
(A) Lipositol
(B) Plasmalogen
(C) Wax
(D) Cephalin
79. A fatty acid which is not synthesized in the body and has to be supplied in the diet is
(A) Palmitic acid
(B) Lauric acid
(C) Linolenic acid
(D) Palmitoleic acid
80. Essential fatty acid:
(A) Linoleic acid
(B) Linolenic acid
(C) Arachidonic acid
(D) All these
81. The fatty acid present in cerebrosides is
(A) Lignoceric acid
(B) Valeric acid
(C) Caprylic acid
(D) Behenic acid
82. The number of double bonds in arachidonic acid is
(A) 1
(B) 2
(C) 4
(D) 6
83. In humans, a dietary essential fatty acid is
(A) Palmitic acid
(B) Stearic acid
(C) Oleic acid
(D) Linoleic acid
84. A lipid containing alcoholic amine residue is
(A) Phosphatidic acid
(B) Ganglioside
(C) Glucocerebroside
(D) Sphingomyelin
85. Cephalin consists of
(A) Glycerol, fatty acids, phosphoric acid and choline
(B) Glycerol, fatty acids, phosphoric acid and ethanolamine
(C) Glycerol, fatty acids, phosphoric acid and inositol
(D) Glycerol, fatty acids, phosphoric acid and serine
86. In mammals, the major fat in adipose tissues is
(A) Phospholipid
(B) Cholesterol
(C) Sphingolipids
(D) Triacylglycerol
87. Glycosphingolipids are a combination of
(A) Ceramide with one or more sugar residues
(B) Glycerol with galactose
(C) Sphingosine with galactose
(D) Sphingosine with phosphoric acid
88. The importance of phospholipids as constituent of cell membrane is because they possess
(A) Fatty acids
(B) Both polar and nonpolar groups
(C) Glycerol
(D) Phosphoric acid
89. In neutral fats, the unsaponificable matter includes
(A) Hydrocarbons
(B) Triacylglycerol
(C) Phospholipids
(D) Cholsesterol
90. Higher alcohol present in waxes is
(A) Benzyl
(B) Methyl
(C) Ethyl
(D) Cetyl
91. Kerasin consists of
(A) Nervonic acid
(B) Lignoceric acid
(C) Cervonic acid
(D) Clupanodonic acid
92. Gangliosides are complex glycosphingolipids found in
(A) Liver
(B) Brain
(C) Kidney
(D) Muscle
93. Unsaturated fatty acid found in the cod liver oil and containing 5 double bonds is
(A) Clupanodonic acid
(B) Cervonic acid
(C) Elaidic acid
(D) Timnodonic acid
94. Phospholipid acting as surfactant is
(A) Cephalin
(B) Phosphatidyl inositol
(C) Lecithin
(D) Phosphatidyl serine
95. An oil which contains cyclic fatty acids and once used in the treatment of leprosy is
(A) Elaidic oil
(B) Rapeseed oil
(C) Lanoline
(D) Chaulmoogric oil
96. Unpleasant odours and taste in a fat (rancidity) can be delayed or prevented by the addition of
(A) Lead
(B) Copper
(C) Tocopherol
(D) Ergosterol
97. Gangliosides derived from glucosylceramide contain in addition one or more molecules of
(A) Sialic acid
(B) Glycerol
(C) Diacylglycerol
(D) Hyaluronic acid
98. ’Drying oil’, oxidized spontaneously by atmospheric oxygen at ordinary temperature and forms a hard water proof material is
(A) Coconut oil
(B) Peanut oil
(C) Rape seed oil
(D) Linseed oil
99. Deterioration of food (rancidity) is due to presence of
(A) Cholesterol
(B) Vitamin E
(C) Peroxidation of lipids
(D) Phenolic compounds
100. Molecular formula of cholesterol is
(A) C27H45OH
(B) C29H47OH
(C) C29H47OH
(D) C23H41OH
