Biochemistry
Multiple Choice Questions.
Q.1 The repeating diassaccharide unit in cellulose is;
a) Dextrin b) Dextrose c) Sucrose
d) Maltose e) Cellubiose
Q.2 The anomeric carbons of carbohydrates:
a) Is the carbon bearing the reactive carbonyl carbon.
b) Is the carbon next to the carbonyl carbon.
c) Is the carbon furthest from the reactive carbonyl carbon.
d) All the carbons bearing hydroxyl groups.
e) Is the carbon with which the reactive carbonyl interacts to form a ring structure.
Q.3 A child with complaint of diarrhea and abdominal pain after taking milk. This condition is due to
deficiency of;
a) Amylase d) Pepsin
b) Lactase e) Collagenase
c) Lipase
Q4. Spermatozoa in seminal fluid utilize one of the following sugar for its metabolism;
a) Galactose b) Glucose c) Fructose
d) Sucrose e) Mannose
Q5. Glomerular filteration rate (GFR) can be determined by the use of which polysaccharides.
a) Glycogen b) Inulin
c) Starch d) Cellulose
e) Dextrin
Q6. Oxidation of monosaccharides forms;
a) Aglycones d) Polyols
b) Glycosides e) Uronic acid
c) Iduronic acid
Q7. α-D Glucose and β-D glucose both are
a) Epimers d) Mutarotation
b) Diastereoisomers e) Enantiomers
c) Anomers
Q8. Inulin is a polymer of:
a) Galactose b) Mannose
c) Fructose d) Xylose
e) α-D glucose
Q9. A compound not produced from dietary starch by salivary α-amylase is:
a) Maltose b) Oligosaccharides
c) Isomaltose d) Fructose
e) Maltotriose
Q10. Highly branched polysaccharide is;
Amylopectin d) Dextran
Cellulose e) Dextrin
Glycogen
Q11. Glycosaminoglycan that does not contain uronic acid is;
Hyaluronic acid d) Heparan Sulfate
Keratin sulfate e) Chondrotin sulfate
Heparin
Q12. A molecule that forms proteoglycan aggregates is;
a) Glycogen d) Heparan
b) Collagen e) Hyaluronic acid
c) Chondroitin 4,6 sulfate
Q13. A compound not produced from dietary starch by salivary α-amylase is;
Maltose d) Fructose
Oligosaccharides e) Maltotriose
Isomaltose
Q14. D- Galactose and D- mannose are
Enantiomers of each other. d) Epimers of each other
Isomers of each other e) Mirror image of each others.
Anomers
Q15. Reduction of galactose with Ca+2 in water produces
Sorbitol
Dulcitol
Mannitol
Glucuronic acid
Galcturonic acid
Q16. Inversion is related to:
Dextrose
Sucrose
Fructose
Lactose
Maltose
Q17. Monosaccharides differing in configuration around one carbon atom are called:
Anomers
Enantiomers
Sterioisomers
Epimers
Diastereoisomers
Q18. Heteropolysaccharide, which is a structural component of skin is:
Keratan sulfate d) Hyaluronic acid
Dermatan sulfate e) Heparin
Hepran sulfate
Q19. Alpha 1-6 glycosidic linkage is hydrolyzed by:
Isomaltase d) Maltase
Sucrase e) Aconitase
Lactase
Q20. Heparin, a mucopolysaccharide, is called as clearing factor because;
It increases the activity of lipoprotein lipase.
It decreases the activity of hepatic lipase.
It has no anticoagulant property in vitro.
It possesses mutarotation.
It conjugates with xenobiotics.
Q21. Sugar units of amylopectin is;
Fructose d) Galactose
Mannose e) Galactose and Fructose
Glucose
Q22. Lactose is made up of;
Glucose-Glucose d) Fructose-Fructose
Galactose-Glucose e) Glucose-Mannose
Glucose-Fructose
Chemistry of Lipids:
Q23. A fatty acid belonging to the monoenoic class is;
Linoleic acid d) Oleic acid
b) Linolenic acid e) Plamitic acid
Aracidoic acid
Q24. The adultration in fats and oils can be checked by;
Iodine number
Acid number
Sponification number
To bind LDL receptors
Ligand HDL receptor
Q25. The transport of endogenous triacylglycerol from liver to peripheral tissues is due to:
Chylomicrons
VLDL
IDL
LDL
HDL
Q26. A substance that is an integral part of glycerol containing phospholipids is;
Acetoacetyl CoA
Choline
Phosphatidic acid
CDP-Ethanolamine
Hydroxybutyrate
Q27. In premature newborns, the deficiency of lipids manifested as’Acute Respiratoy Distress Syndrome’ is
attributed to;
a) Bile acids
b) Leukotriene
c) Thromboxane
d) Dipalmitoylphosphatidylcholine
e) ProstacyclinQ28. The rancid smell of fat is due to the presence of;
Vitamin A and E
Quinones
Phenols
Volatile fatty acids
Cholesterylesters
Q29. Phospholipids are important cell membrane components because they;
Have glycerol
Can form bilayer
Have both polar and non-polar groups
Combine covalently with proteins
Have phosphate group
Q30. A fatty acid that is found in highest concentration in cholesterol ester is;
Arachidonic acid
Oleic acid
Palmitic acid
Linolic acid
Linolenic acid
Q31. The major source of extra cellular cholesterol for human tissues is;
Very low density lipoproteins (VLDLs)
Low density lipoproteins (LDLs)
High density lipoproteins (HDLs
Albumin
Chylomicrons
Q32. Deficiency of Essential fatty acids is associated with;
Hypertension.
Eczema like dermatitis
Poliomyelitis
Myositis
Pancreatitis
Q33. In Tay-Sach’s disease , the deficient protein is;
Gangliosidase
Ceriminidase
Hexosaminidase A
Galactosaminidase
Lecithinase
Q34. The hydrolysis of triglycerides requires formation of micelles so that lipase can function. The
compound which is more responsible for the micelle formation is;
Taurochenodeoxycholic acid
Tripalmitin
Monopalmitin
Cholesterol palmitate
e) Decanoic acid
Q35. Fat (triglyceride) is a more efficient energy storage form than carbohydrates because fat:
Is stored in tissues in a relatively water free form
Is a more oxidized state than glycogen
Is degraded to Acetyl-CoA
Is mainly bounded to albumin
Gives acyl derivatives.
Q36. A carbohydrate that can distinguish a ganglioside from a globoside is;
Glucose
N-Acetyl Neuramic acid
N-Acetyl galactose amine.
Galactose
Mannose
Q37. A phospholipid having antigenic activity is;
Lecithin
Cardiolipin
Sphingomyelin
Cephalin
e) plasmalogens
Q38. A glycolipid which is known to be the receptor in human intestine for cholera toxin is;
GMI
GM3
Globoside
Cerebroside
Ganglioside
Q39. An apolipoprotein which activates “Lipoprotein lipase” (LPL) is;
apoB-48
apoB100
apoC-II
apoE
Absence of insulin
Q40. The blood of a person who consumes large amounts of animal fat would most likely contain;
Increased levels of chylomicrons.
Increased level of VLDL
Increased level of HDL
Increased level of LDL
Decreased level of Cholestrol
Chemistry of Amino acids & Proteins:
Q41. Amino acid which is hydrophobic and has a tendency to be located away from the surface of proteins is?
Aspartate
Cysteine
Lysine
Isoleucine
Arginine
Q42. With the exception of glycine, all amino acids found in proteins are;
Dextrorotatory
Of the D-configuration
Optically inactive
L-configuration
Either L or D
Q43. Amino acids whichwould exhibit the greatest positive charge at physiological pH is?
Arginine
Histidine
Lysine
Aspartic acid
Glutamic acid
Q44. Amino acids required during the rapid tissue growth are:
Arginine and Glycine
Arginine and Histidine
Lysine and Histidine
Phenylalanine and Histidine
Glycine and Histidine
Q45. Proline disrupts the α-helical structure because of
Steric hindrence
Straight nature of its side chain
Availability of H-atom for H-bond formation
COOH group is involved in ionic interaction
All of the above
Q46. An example of phosphoproteins is:
Peroxidase
Ceruloplasmin
Caseins
Mulins
Immunoglobulin
Q47. Regarding tertiary structure of a protein;
It is over all three dimensional conformation of protein
It involves only the α-helices
It is found in fibrous protein only.
It is stabilized by non-covalent forces
Disulphide linkage is formed between side chain
Q48. 10 years old boy has developed generalized oedema and protein urea the oedema is due to;
Decreased protein synthesis
Decreased colloidal osmotic pressure.
Increased capillary hydrostatic pressure.
Lymphatic obstruction
Decrease protein intake
Q49. Extra corpuscular hemoglobin binds to:
Haptoglobin
Albumin
Transferrin
Ceruloplasmin
Alpha-2-macroglobulin
Q50. A protein has one transmembrane domain composed entirely of α-helical structure. Amino acids which
would you expect to find in the transmembrane domain is;
Proline
Glutamate
Lysine
Leucine
Arginine
Q51. Globulin binds with heme to form:
Hemopexin
Haptoglobin
Lactoglobulin
Tranferrin
Ovovituallin
Q52. A child with tall stature, loose joints, and detached retinas is found to have a mutation in type II collagen. Amino acid most likely to be altered in mutations that distort collagen molecules?
Glycine
Hydroxyproline
Hydroxylysine
Tyrosine
Tryptophan
Q53. The most commonly present secondary structure of proteins in human body is;
Super coil structure
β-helical structure
α-helical structure
Random coil structure
Globular
Q54. Denaturating agent that disrupts Di-sulphide bonds and dissociates protein into a single polypeptide chain is;
Hydrochloride
Salicylic acid
Performic acid
Guanidine hydrochloride
None of the above
Q55. The amino acids which are commonly found in β-turns of protein is?
Arginine and lysine
Leucine and valine
Aspartic acid and glutamic acid
Tryptophan and tyrosine
Glycine and proline
Q56. Quaternary level of protein structure exists as;
One polypeptide chain
Multichain complex of same function
Protein-protein aggregates with different functions
Homogenous of 2 or 3 monomers
Heterogenous monomers
Q57. At pH less than 5, the zwitterions form of alanine (pI=6) will have;
Low solubility in water
Net positive charge
Negative charge on carbosyl group
Net negative charge
Over all charge of zero
Q58. Acids and bases denature a protein by disrupting;
Peptide bonds & ionic bonds
Hydrophobic interactions and peptide bonds
Ionic bonds and hydrogen bonds
Amide bonds and alkene bonds
Ionic bonds and hydrophobic bonds
Q59. Iodine deficiency results in low levels of thyroid hormones. Another cause of low thyroid hormone level
is deficiency of the amino acid;
Tyrosine
Proline
Cystine
Histidine
Methionine
Q60. A planar structure composed of segments of polypeptide chains arranged in parallel or antiparellel fashion
Is:
Alpha helix d) Trans helix
Beta sheet e) Beta turns
Collagen triple helix
Q61. The synthesis of protein being directly affected in scurvy is:
Myoglobin d) Collagen
Hemoglobin e) Fibrinogen
Insulin
Q62. An essential amino acid in human is:
Proline
Threonine
Aspartate
Tyrosine
Serine
Enzymes :
Q63. The digestive enzymes belong to:
Oxidoreductases
Lyases
Hydrolases
Transferases
Ligases
Q64. The function of many enzymes can be quikly activated or deactivated by phosphorylation of specific
residues catalyzed by a class of enzymes called;
a) Cyclases
Kinases
c) Phosphatases
d) Zymogens
e) Proteases
Q65. The turn over number is expressed in units of;
Moles per liter
Grams per mole
Moles of product per minute per mole of enzymes
Micromoles per minute
Micromoles of product per minute per mg of enzymes.
Q66. A matter that explained by the induced fit model related to the enzyme action is;
Enzyme becomes active on denaturation.
Enzymes become inactive on denaturation
Unsaturated kinatics
Allosteric enzymes
e) Allosteric effectors
Q67. Regarding irreversible enzyme inhibition;
Inhibitor resembles substrate
Inhibitor binds at the active site
Inhibitors competes with substrate
Inhibitors changes the conformational state of enzyme
Increasing substrate conc will resume enzyme activity
Q68. Enzyme activity in biological systems is effected by;
Fix concentration of enzyme
Optimum Temprature
c) Change in pH
d) Time
e) Decrease rate of activation
Q69. A substrate specific enzyme amongst the following is:
Hexokinase
Thiokinase
Lactase
Aminopeptidase
e) Transacetylase
Q70. The rate of an enzyme- catalyzed reaction was measured using several substrate concentrations that were much lower than km. The dependence of reaction velocity on substrate concentration, can be best described as;
Independent of enzyme concentration
A constant fraction of Vmax
Equal to km
Proportional to the substrate concentration
Zero order with respect to substrate
Q71. A patient as diagnosed to have Osteoarthritis. An enzyme specifically elevated in this condition is;
Glutamate Oxaloacetate transaminase
Lipase
Glitamate pyruate transaminase
Alkaline phosphatase
Creatine kinase
Q72. An 8 years old female with 15 days history of abdominal pain with yellowish discoloration of skin & sclera is diagnosed to have hepatitis A. An enzyme in the serum which is the most sensitive & specific marker for hepatic damage is;
Alkaline phosphatase
Lactate dehydrogenase
Alanine amino transferase (ALT)
Amylase
Aspartate aminotransferase (AST)
Q73. Serum enzyme assay useful to establish Myocardial infarction (MI) after 2 weeks of suspected attack is:
Aspartate Transaminase
γ-glutamyl transpeptidase
Alkaline phosphatase
Lactate dehydrogenase
Creatine kinase
Q74. In non-competitive inhibition;
Km is increased
Vmax is increased
Km is decreased
Km is unchanged
Vmax unchanged
Q75. The Michalis constant km is;
Numerically equal to ½ Vmax
Dependent on the enzyme concentration
Independent of pH
Numerically equal to the substrate concentration that gives half-maximal velocity
Increased in the presence of a non-competitive inhibitors
Q76. Enzyme elevated in neurogenic muscular weakness is;
Amylase
Creatine kinse
Aldolase
Lactate dehydrogenase
Gamma glutamyl transpeptidase
Q77. The serum Aspartate transaminase (AST) activity is not characteristically elevated as a result of:
Myocardial infarction
Passive congestion of liver
Muscular dystrophies
Peptic Ulcer
Infectious hepatitis
Q78. A non-cardiac disease in which CK-MB level found to be raised is;
Acute renal failure
Polymyositis
Cerebrovascular accident
Anoxic encephalopathy
Severe physical activity
Q79. A patient was diagnosed to have acute myocardial infarction. The enzyme preparation given
intravenously to dissolve the clot in his coronary artery is:
Streptodomase
Heparin
Hyaluronidase
α-chymotrypsin
Streptokinase
Q80. An enzyme useful in the treatment of Leukemia is;
α-Chymotrypsin
Hylauronidase
Streptokinase
Asparaginase
Urokinase
Chemistry of Nucleic acids & Nucleotides:
Q81. At neutral pH, the nucleotides behave as:
a) Proton acceptor d) Proton Donor
b) Electron acceptor e) Neutral
c) Electron Donor
Q82. If a strand of DNA molecule has a bases sequence of 5 …..d GATCCGCGp….3, which bases sequence of anti parallel strand will match to it from the following:
a) 3’ …..dTCGTAGCTp…..5’ b) 3’ …..dCTAGGCGCp…5’
c) 5’ …..dCTAGGCGCp…3’ d) 5’ …..dCTAGGCGCp…3’
e) 3’ …..dGATCCGCGp…5’
Q83. A purine nucleotide that acts as high energy intermediate is:
a) cAMP d) cGMP
b) ATP
c) UDP e) UMP
Q84. The histone oligomers associate to form the histone octamer of the compostion
(H2A-H3)2 (H2B-H4)2
(H2B-H3)2 (H2A-H4)2
(H2A-H2B)2 (H3 H4)2
(H2A-H3A)2 (H2B-H4)2
(H2A-H4)2 (H2B-H3)2
Q85. In formation of cAMP, the stimulation of adenylate cyclase by the hormone receptor complex requires the presence of:
a) GTP d) GMP
b) ATP
c) UDP e) UMP
Q86. RNA that contains unusual purines and pyrimidine is:
a) m-RNA d) r-RNA
b) t-RNA
c) hn-RNA e) snRNA
Q87. cAMP is degraded by
Phosphodiesterase
Phosphokinase
Adenyl cyclase
Cholinesterase
NAD dependant dehydrogenase
Q88. Interactions between the stacked bases that stabilize the structure of double helix of DNA are;
Hydrogen bond & Ionic interactions
Hydrogen bond & Hydrophilic interaction
Covalent bond & Hydrophilic interaction
Disulfide bond & Hydrophobic interaction
Hydrogen bond Only
Q89. Each nucleosome is joined by a:
a) H2A & H2B histones
b) Linker DNA & H1 histone
c) Linker DNA & H3 histone
d) H2B, H3 & H4 histones
e) Linker DNA only
Q90. A nucleotide that is required for the protein synthesis is;
a) AMP d) GTP
b) ADP e) CTP
c) UTP
Q91. The DNA strand that runs into 3 – 5 direction is called;
Template strand
Non-coding strand
Minor groove
Major groove
Acceptor arm
Q92. In pyrimidine nucleotides the linkage that is formed at position N-1 of pyrimidine base linked to ‘C’no.1
of sugar (either ribose or deoxyribose) is called;
Glycosidic linkage
Amide linkage
β-N-glycoside linkage
Peptide linkage
α-glycoside linkage
water,pH, & Buffer
Q93. The only volatile acid amongst the following is;
Carbonic acid
Lactic acid
Keto acids
Sulphuric acid
Phosphoric acid
Q94. Regarding acid buffering the first line of dense is
Plasma buffers
Respiratory compensation
Kidney mechanism
Lever conjugation
Immune system
Q95. Quantitatively the most important physiological buffer in the blood is,
Hb buffer system
Acetate buffer
Phosphate buffer
Bicarbonate buffer
Protein buffer
Q96. A buffer solution has a maximum buffering efficiency when;
pH= pk+3
pH= pk +2
d)pH>pk
pH<pk
pH=pk
Q97. Weak acid acts best as buffering agent;
On physiological pH of the body
At low pKa of acid
In acidic environment
In basic environment
When pH is equal to pKa of acid.
Q98. The fluid that has the higest pH is;
Gastric juice d) Seminal fluids
Pancreatic juice e) Urine
Saliva
Q99. Plasma fluid differs from interstitial fluid in;
Conc of Na+.
Conc of HCO3
Conc of K+
Conc of Ca+
e) Conc of protein
Q100. Primary disturbance in respiratory acidosis is;
Excess of H+.
Excess of H2CO3
Depletion of H2CO3
Excess of HCO3
Excess of fixed acid
Biochemistry
MCQs Key:
