Laboratory Assistant (Dairy/ CFP) Question Paper and Answer Key

Laboratory Assistant (Dairy/ CFP) Question Paper and Answer Key

Question Code: 081/2022 (A)

Name of Post: Laboratory Assistant (Dairy/ CFP)

Department: Kerala Co-operative Milk Marketing Federation Ltd

Cat. No: 402/2021

Date of Test: 12.08.2022

Laboratory Assistant (Dairy/ CFP) Question Paper and Answer Key

 1. According to Arrhenius concept acid is a substance which dissociate to give ______ ions in solution.


Answer : C

2. pH of 1.0 M sodium hydroxide solution is
A) 0
B) 1
C) 14
D) None of these

3. In a thermodynamic process, if no heat enters or leaves the system is called
A) Isothermal process
B) Adiabatic process
C) Isobaric process
D) Isochoric process
4. When alcohol added to water surface tension
A) Increases
B) Decreases
C) First increases then decreases
D) No change

 5. 2 g of sodium hydroxide dissolved in 100 mL water, the molarity of the solution is
A) 0.5 M
B) 1 M
C) 2 M
D) 0.1 M
6. Colligative property of a solution is proportional to
A) Volume of the solution
B) Number of solute particles in the solution
C) Normality of the solution
D) Mole fraction of the solution

7. In Ag-Cu cell oxidation occurs at
A) Electrolyte
B) Ag electrode
C) Zn electrode
D) Cu electrode

 8. Which of the following molecule does not show infrared spectrum ?
C) H2
D) CO2
9. The elastic scattering of photons are called
A) Raman scattering
B) Rayleigh scattering
C) Newton scattering
D) Einstein scattering

10. Which of the following shift lead to increased intensity on absorption of UV visible radiation ?
A) Hyperchromic shift
B) Bathochromic shift
C) Hypsochromic shift
D) Hypochromic shift


11. Number of ESR hyperfine splitting lines of methyl radical (CH3) radical is
A) 1
B) 2
C) 3
D) 4

12. For measuring chemical shift in NMR spectroscopy the chemical compound commonly used as reference is
A) tetramethyl silane
B) hydroquinone
C) benzene
D) ethanol
13. In which chromatography, stationary phase is held in a narrow tube and the mobile phase is forced through under pressure ?
A) High pressure liquid chromatography
B) Column chromatography
C) Paper chromatography
D) Thin layer chromatography
14. The first milk produces by cow after calving is called
A) Colostrum
B) Carotene
C) Metalene
D) Oestrum
15. Specific gravity of milk can be determined by using
A) Manometer
B) Hygrometer
C) Lactometer
D) Barometer
16. Which of the following cow breed gives maximum yield of milk ?
A) Zebu
B) Jersy
C) Brown Swiss
D) Holstein-Friesian

17. The vitamin which is deficient in milk is
A) D
B) A
C) B
D) C

18. The official record of registered animals of a breed kept by the breed association is called
A) Cattle book
B) Domestic book
C) Farm book
D) Heard book
19. To the water extract of the cattle feed, addition of concentrated sulfuric acid _______ colour indicates the presence of Mahua cake.
A) black
B) violet
C) yellow
D) white

 20. Ammonium molybdate reagent is used for identifying _________ in cattle feed.
A) manganese
B) magnesium
C) calcium
D) phosphorous

21. The color of milk is a blend of individual effects produced by colloidal casein particles and
A) methyl red
B) alizarin
C) carotene
D) curcumin

 22. Volhard’s method is used for detecting _________ content in butter.
A) sugar
B) salt
C) water
D) acid

23. Example for Newtonian fluid is
A) milk
B) suspensions
C) pastes
D) emulsion

 24. Milk is a rich source of energy, the fat content in cow milk is _______ cal/g.
A) 2.6
B) 6.5
C) 4.2
D) 9.3

25. Total solid and total SNF in milk determined by ________ method.
A) Gabriel
B) Vanthoff
C) Gerber
D) Wikinson

 26. Which among the following requires sodium ion dependent transport for intestinal absorption ?
A) Glucose
B) Fructose
C) Xylose
D) Arabinose
27. Identify the protein which has phosphate as its prosthetic group.
A) Hemoglobin
B) Casein
C) Xanthine oxidase
D) Ferritin
28. Megaloblastic anaemia is caused due to the deficiency of which among the following vitamin ?
A) Cyanocobalamin
B) Thiamine
C) Ascorbic acid
D) Folic acid

29. Which among the following enzyme is used in cancer therapy ?
A) Streptokinase
B) Asparaginase
C) Trypsin
D) Alkaline Phosphatase

30. The level of structural organization of protein unaffected by denaturation is
A) Primary
B) Secondary
C) Tertiary
D) Quaternary


31. Identify the subunits in the heteropolysaccharide Keratin sulphate.
A) D-glucuronic acid and N-acetyl galactosamine-4-sulphate
B) D-glucuronic acid and N-acetyl glucosamine
C) L-iduronic acid and N-acetyl galactosamine-4-sulphate
D) D-galactose and N-acetyl glucosamine-6-sulphate

32. The positions of double bond in linolenic acid are
A) 1 and 9
B) 2, 9 and 12
C) 9, 12 and 15
D) 5, 8, 11 and 14

 33. Identify the plasma protein responsible for maintaining the osmotic balance in our body.
A) Haptoglobulin
B) Albumin
C) Fibrinogen
D) Ceruloplasmin

34. Identify the enzyme which catalyses substrate level phosphorylation reaction in TCA cycle.
A) Isocitrate dehydrogenase
B) Aconitase
C) Succinate thiokinase
D) Fumarase
35. The disease caused due to the deficiency of phytanic acid α-oxidase is
B) Refsum’s disease
C) Zellweger syndrome
D) Methyl malonyl aciduria

36. Which among the following amino acids do not undergo transamination reaction ?
A) Lysine and threonine
B) Lysine and aspartate
C) Threonine and glutamate
D) Aspartate and glutamate

37. The normal serum calcium concentration is
A) 4.5 – 5.5 mg/dL
B) 2.3 – 3.6 mg/dL
C) 9.1 – 11 mg/dL
D) 15.2 – 17.5 mg/dL

 38. Cyclopentano perhydro phenanthrene nucleus is the basic structural unit in which biomolecule ?
A) Glycolipids
B) Phospholipids
C) Cholesterol
D) Sphingolipids
39. The mineral oxide content in a food sample can be determined by measuring the
A) Nitrogen content
B) Ash content
C) Protein content
D) Total solid content
40. Which among the following is the range of the melting point of milk fat ?
A) 18 – 20°C
B) 22 – 24°C
C) 28 – 30°C
D) 32 – 36°C

41. The antibody which is present in the highest concentration in serum is
A) IgM
B) IgD
C) IgE
D) IgG

42. The groups located on the surface of an antigen molecules which are recognized by the antibody is
A) Isotope
B) Epitope
C) Paratope
D) Hapten

43. Which among the following radioactive isotope is commonly used in Radioimmunoassay ?
A) Sulphur-35
B) Phosphorus-32
C) Iodine-125
D) Nitrogen-14

44. Identify the solvent used for the process of defatting in cold extraction.
A) Petroleum ether
B) Ethyl acetate
C) Ethanol
D) Water

45. Blocking agent is used in western blotting. Identify the purpose.
A) Blocks the transfer of protein from gel to membrane
B) Blocks the binding of antibody to the membrane
C) Blocks the binding of primary and secondary antibody
D) Blocks non-specific secondary antibody
46. Which among the following technique makes use of immunofluorescence ?
A) Confocal microscopy
D) Electron microscopy
47. Identify the constituents in the milk protein.
A) Whey proteins
B) Casein
C) Ferritin
D) Both A) and B)

48. The protein content can be measured using which among the following methods ?
A) Kjeldahl method
B) Gerber’s method
C) Rose-Gottlieb’s method
D) Babcok’s method

49. The class of antibody that is expressed on the surface of B-lymphocytes is
A) IgA
B) IgE
C) IgG
D) IgM

50. Identify the enzyme used in the technique of ELISA.
A) Horse radish peroxidase
B) Tyrosinase
C) Lactate dehydrogenase
D) Chymotrypsin

51. Rocky mountain spotted fever is caused by
A) Rickettsia rickettsii
B) Rickettsia prowazekii
C) Rickettsia typhi
D) Rickettsia akari

52. Bacterial conjugation was described by
A) Zinder and Lidenberg
B) Lederberg and Tatum
C) Tatum and Zinder
D) Beadle and Tatum
53. Which of these are basic dyes ?
A) Methylene blue, Crystal violet
B) Methylene blue, Rose bengal
C) Crystal violet, Rose bengal
D) Methylene blue, Eosin

54. Mesosomes are present in
A) Only gram negative
B) Only gram positive
C) Both gram positive and negative bacteria
D) None of the above

55. Bacterial membrane contains sterol like molecules called hapnoids. Hapnoids are
A) Penta cyclic sterols
B) Tetra cyclic sterols
C) Heptacyclic sterols
D) None of these

56. Final blow to spontaneous generation was given by
A) Louis Pasteur
B) Robert Koch
C) John Tyndall
D) John Needham
57. Fixative osmium tetroxide is used to stabilize
A) Protein
B) Nuclear material
C) Cell structure
D) Dehydration of cell
58. Diameter of metal grid for specimen mount used in Electron Microscope is
A) 3.05 mm
B) 3.50 mm
C) 3.05μm
D) 3.50μm

59. Medium containing serum or egg are sterilized by
A) Hot air oven
B) Autoclave
C) Inspissator
D) Incinerator

60. The membrane used in budding of corona viruses are
A) Endoplasmic reticulum and nucleus
B) Golgi apparatus and nucleus
C) Golgi apparatus and Endoplasmic reticulum
D) Nucleus and plasma membrane
61. Which of the following is most effective in destroying micro-organisms ?
A) High temperature low moisture
B) High temperature high moisture
C) Low temperature high moisture
D) All of the above
62. Which of the below mentioned condition determines Thermal Death Time (TDT) ?
A) Temperature is varied and time is fixed
B) Temperature and time is fixed
C) Temperature and time is varied
D) Temperature is fixed and time is varied

 63. Which of the algae has structure called Gullet ?
A) Euglenoids
B) Golden algae
C) Blue green algae
D) Dinoflagellates
64. In modified atmosphere packaging content of carbondioxide commonly used to prevent spoilage of packed food is
A) Greater than 25%
B) Less than 30%
C) Greater than 60%
D) None of the above

65. Which of the statements is correct regarding algal toxins ?
 A) Commonly found in fish and marine animals
 B) Algal toxins are neurotoxic
 C) Algal toxins are temperature stable
 D) All of the above

66. Ultra high temperature pasteurisation process involves




67. In flat sour spoilage which conditions are observed
A) No gas formation
B) Acid formation without gas
C) Both acid and gas formation
D) None of the above

 68. The intensity of radiation commonly used to sterilize meat products in rad pasteurisation is
A) 4.5 – 5.6 mega rads
B) 4.1 – 5.2 mega rads
C) 3.5 – 4.5 mega rads
D) 4.8 – 5.9 mega rads
69. Method of sterilization used to remove 90% of pathogenic micro-organisms from spices is
A) Autoclave
C) Radicidation
D) Ethylene oxide
70. Semisoft blue cheese are produced by
A) Penicillium candidum
B) Penicillium camembertii
C) Penicillium roqueforti
D) Lactobacillus lactis


71. Xerophillic organisms preferred to grow at
A) High aw condition
B) Low aw condition
C) High osmotic concentration
D) All of the above
72. Dairy product of mold lactic fermentation is
A) Kefir
B) Villi
C) Cheese
D) Yogurt
73. Which of the following is reason for rancidity of fat in butter ?
A) Production of short chained fatty acids
 B) Production of long chained fatty acids
 C) Absence of short chained fatty acids
 D) Absence of long chained fatty acids
74. Coumarins is a natural antimicrobial agent found in
A) Buffalo milk
B) Plants and vegetables
C) Cow milk
D) Meat and its products
75. Sandwich ELISA method is used for the detection of
A) Antibody
B) Antigen
C) Conjugated antibody
D) Conjugated antigen

76. Which of the following possess buffering capacity ?
A) Proteins
B) Nucleic acids
C) Lipids
D) All of the above
77. The number of different possible DNA sequences with ‘n’ nucleotides is
A) 4 + n
B) 16n
C) 4n
D) n4

78. Cytosine is
A) 2-amino-6-oxy pyrimidine
B) 2, 4-dioxy-5-methyl pyrimidine
C) 2, 4-dioxy-6-carboxy pyrimidine
D) 2-oxy-4-amino pyrimidine

79. Which is the least conserved histone ?
A) H4
B) H1
C) H3
D) H2A & H2B

 80. DNA Sequence interacts with σ factor of RNA polymerase is

81. Bio pesticides are
A) Biochemical pesticides
B) Microbial pesticides
C) Plant incorporated protectants
D) All of these

82. Single cell protein is derived from
A) Bacteria
B) Fungi
C) Algae
D) All of these
83. Therapeutic proteins
A) Binds non covalently to the target
B) Affects covalent bonds
C) Exert no specific interaction
D) All of these

84. Which enzyme is not used for improving quality of bread in food industry ?
A) Protease
B) β -galactosidase
C) α-amylase
D) Glucoamylase

85. Patent Act Amendment in 2021 refers to
A) Introduction of product patent protection for pharmaceuticals
B) Reduction of fee for patent filing and prosecution for educational institutions
C) Modification of criteria for patenting an invention
D) All of these

86. The following biocontrol agent is commonly used in controlling Phytophthora infections in plants
A) Trichoderma
B) Bacillus thuringiensis
C) Parasitoides
D) Baculoviruses

87. GP 293 cell lines are mainly used in the over production of
A) Enzymes and vaccines
B) Antibiotics and vaccines
C) Growth factor
D) All the above
88. Meat tenderization is often enhanced by
A) Papain
B) Bromelain
C) Both A and B
D) A only
89. Which of the following is a chaotropic agent ?
A) Glycerol
B) Guanidine
C) Bromophenol blue
D) Coomassie blue

90. Agarose consists of
A) galactose and 3, 6-anhydrogalactose
B) glucose and 3, 6-anhydrogalactose
C) glucose and 3, 6-anhydroglucose
D) galactose and 3, 6-anhydroglucose

91. Stain used to detect glycoproteins in gel
A) Silver stain
B) Ponceau stain
C) Periodic acid-Schiff stain
D) Coomassie blue stain

92. Asymmetric PCR differs from regular PCR in
A) The amount of primer used
B) DNA polymerase enzyme
C) Denaturation temperature
D) Template concentration

 93. Which is the highly sensitive technique used for the identification and quantification of pesticide residues ?
A) Gas chromatography
B) Liquid chromatography
D) Column chromatography


 94. Recombinant DNA technology was invented by
A) Boyer, Cohen and Paul Berg
B) Nathan, Arber and Smith
C) Watson, Crick and Wilkins
D) None of these

95. Technique which employ nucleic acid probe for the diagnosis of viral diseases ?
A) dot blot hybridization
B) sandwich hybridization
C) in situ hybridization
D) all of these
96. Regulations and Guidelines for Recombinant DNA Research and Biocontainment came into force in
A) 2008
B) 2017
C) 2016
D) 2011

97. Which membrane is commonly used in Northern blotting ?
A) Nitrocellulose
B) Nylon
C) Polyvinylidenedifluoride membrane
D) None of these
98. Which of the following can be used as a vaccine ?
A) Live attenuated viruses
B) Inactivated cell culture grown viruses
C) Recombinant protein
D) All of these

99. Which one of the following statements is not correct with respect to DNA probes used in microbial identification ?
i. They cannot be used to identify microorganisms that are not readily cultured or biochemically identified.
ii. They cannot be used to identify microorganisms that do not possess diagnostic antigens.
iii. It allows differentiation of pathogenic from avirulent strains.
iv. Can identify of antibiotic resistance genes.
A) i and iii is wrong
B) i and ii is wrong
C) ii and iv is wrong
D) iii is wrong
100. First recombinant vaccine was against
A) Hepatitis B
C) Chicken pox
D) Hepatitis C