Answer Key of BHU PET Applied Microbiology 2014 (Part 1)
Q51. Which of the following statements about fungi is false?
(1) They are heterotrophs
(2) Their cell wall is composed of chitin
(3) They do not contain membrane bound nucleus
(4) They are decomposers
Q52. Which of the following is an asexual spore?
(1) Basidiospore
(2) Ascospore
(3) Zygospore
(4) Conidia
Q53. Which of the following characteristic would not be important for an organism used in an industrial process
(1) Fast growth rate
(2) Genetic stability
(3) Amenability to genetic manipulation
(4) Must be a prokaryote
Q54. The production of secondary metabolites occurs at or near the onset of which of the microbial growth phases?
(1) Lag phase
(2) Log phase
(3) Stationary phase
(4) Exponential phase
Q55. Which of the following is not a primary metabolite in microorganisms?
(1) Vitamin B12
(2) Riboflavin
(3) Antibiotics
(4) Amino acids
Q56. Commercially vitamin B12 is produced by
(1) Bacillus sp.
(2) Propionibacterium sp.
(3) Rhizopus sp.
(4) Agrobacterium sp.
Q57. The cells of bacteria can be categorized according to their arrangement. A cubical packet of eight cocci is known as
(1) Sarcina
(2) Diplococci
(3) Streptococci
(4) Staphylococci
Explanation: Size, Shape, and Arrangement of Bacterial Cells With Picture and Example
Q58. An ultraviolet light source is used in
(1) Phase-contrast microscope
(2) Darkfield microscope
(3) Electron microscope
(4) Fluorescent microscope
Explanation: Fluorescence Microscope: Definition, Uses, Principle, Parts.
Q59. HIV, a virus causing AIDS is Classified as
(1) Arbovirus
(2) Retrovirus
(3) Togavirus
(4) Baculovirus
Q60. The proteases used in the detergents have pH optimum in a range of
(1) 4 to 57
(3) 9 to 10
(2) 6 to 8
(4) 3 to 4
Q61. The characteristic that does not affect the rate at which a population of an organism killed is
(1) Population size
(2) Time of exposure to killing agent
(3) Susceptibility of an organism
(4) Concentration of an antimicrobial agent
Q62. Antigens
(1) Are always proteins
(2) Always induce the formation of antibodies
(3) Are not involved in allergic reaction
(4) Are immunoglobulins
Q63. The positive test for acid fast stain is shown by the bacteria causing the disease
(1) Tuberculosis
(2) Typhoid
(3) Tetanus
(4) Colitis
Q64. Micorrhiza represents
(1) Parasitic association between root and fungus
(2) Symbiotic association between root and fungus
(3) Symbiotic association between root and bacteria
(4) Parasitic association between root and algae
Q65. Chains of cells is a characteristic property of the genus
(1) Staphylococcus
(2) Bacillus
(3) Streptococcus
(4) Corynebacterium.
Explanation: Size, Shape, and Arrangement of Bacterial Cells With Picture and Example
Q66. Antibiotic resistance is referred to
(1) The resistance of human body to antibiotics
(2) Loss of sensitivity of a pathogen to antibiotics
(3) Deformity produced by antibiotic treatment in human body
(4) Acquisition of a plasmid
Explanation: Antibiotic Resistance: Definition, Mechanism, Example.
Q67. The presence of E. coli in a municipal water supply indicate
(1) Tube well as a source of water
(2) Water is stored before supply
(3) Water is fit for drinking
(4) Faecal contamination.
Q68. Which of the following conversions is undesirable in wine making?
(1) Sucrose to ethanol
(2) Ethanol to acetic acid
(3) Malic acid to lactic acid
(4) Fructose to pyruvic acid
Q69. A vector is a
(1) Natural reservoir of a pathogen
(2) Human parasite
(3) Disease transmitting host
(4) Pathogenic organism
Q70. The catalytic activity of enzymes is due to
(1) Reduction in the activation energy of the reactants
(2) Reduction in the potential energy of the reactants
(3) Increase in the free energy of the reaction
(4) Increase in the kinetic energy of the reactants
Q71. When E. coli is inoculated to the medium containing both glucose and lactose, which of the following utilization pattern will be observed
(1) Both will be utilized simultaneously
(2) The one which is present in higher concentration will be utilized first
(3) Lactose will be utilized first and glucose thereafter
(4) Glucose will be utilized first and lactose thereafter.
Q72. During organic evolution, the organism first appeared on the earth are
(1) Algae
(2) Fungi
(3) Viruses
(4) Photosynthetic bacteria
Q73. Immobilized enzyme is
(1) A purified enzyme preparation
(2) Enzyme linked to a water insoluble solid support
(3) Enzyme located on plasma membrane
(4) Enzyme dissolved in buffer
Q74. In prokaryotic cells, the enzymes involved in the oxidation of metabolites are associated with
(1) Mitochondria
(2) Nucleoid
(3) Mesosomes
(4) Chloroplasts
Q75. In nitrogen fixation
(1) Plant fix nitrogen into nitrate
(2) Plant convert nitrite into nitrate
(3) The enzyme nitrogenase produce ammonia from nitrogen
(4) Bacteria are present on the roots
Q76. Antibiotics are the chemicals which
(1) Kill the microbes
(2) Arrest the growth of microbes
(3) Are produced by the microbes and arrest the growth or kill the Microbes
(4) Products of anabolic reactions
Q77. Microbial insecticide is a preparation that contains
(1) Insects harmful to microbes
(2) Microbes harmful to insects
(3) Microbes producing diseases in plants
(4) Plant pathogens
Q78. Ti plasmid is present in
(1) Escherichia coli
(3) Serratia marcescens
(2) Bacillus subtilis
(4) Agrobacterium tumefaciens.
Q79. Km value of an enzyme represents
(1) Substrate concentration at half maximum velocity
(2) Velocity at half substrate concentration
(3) Enzyme concentration at half maximum velocity
(4) Substrate concentration at maximum velocity
Q80. The end product of carbohydrate metabolism changes under aerobic and anaerobic conditions in an organism
(1) Lactobacillus
(2) Saccharomyces
(3) Mycobacterium
(4) Clostridium
Q81. Generation time of an organism represents
(1) Number of generations completed in one hour
(2) Time period lapsed between two successive divisions
(3) Time required by a cell to divide
(4). Time required to prepare the cell for division.
Q82. Isozymes are a group of enzymes
(1) Acting on a substrate producing the same product
(2) Having same pH optimum
(3) Having same Km value
(4) Having same turnover number
Q83. A strong positive catalase test is shown by
(1) Aerobes
(2) Facultative anaerobes
(3) Anaerobes
(4) Microaerophilic organisms
Q84. Pasteurised milk is:
(1) Sterile milk
(3) Defatted milk
(2) Free from human pathogens
(4) Boiled milk
Q85. Root nodules are found in:
(1) Some leguminous plants
(2) Some leguminous and some other plants
(3) All plants
(4) All leguminous plants but never in other plants.
Q86. Biochemical oxygen demand (BOD) represents:
(1) Amount of oxygen required by microorganisms to oxidize organic matter
(2) Demand of oxygen by microbes
(3) Amount of oxygen required by microorganisms to oxidize organic and inorganic matter
(4) Total amount of oxygen dissolved in water.
Q87. Which of the following is the most suitable organism for use in testing the efficiency of steam sterilization?
(1) Clostridium perfringens
(2) Bacillus stearothermophilus
(3) Bacteroides fragilis
(4) Bacillus subtilis
Q88. In the process of cheese manufacture, the microorganisms are important for
(1) Souring and ripening
(2) The souring of milk
(3) The ripening of cheese
(4) Prevention of spoilage.
Q89. “Superbug’ is a bacterium:
(1) Used for controlling bug pest
(2) Capable of using mineral oil as a carbon source
(3) Resistant to most of the antibiotics,
(4) Pathogenic to humans.
Q90. Restriction endonucleases are utilized in genetic engineering to:
(1) Degrade DNA molecule
(2) Build nucleotide sequence
(3) Cut DNA at specific sites
(4) Combine fragments of DNA into long chains
Q91. A cell divides every minute and takes one hour to fill a cup. How much time will it take to fill half a cup?
(1) 30 minutes
(2) 45 minutes
(3) 55 minutes
(4) 59 minutes
Q92. Normally, the soreness of curd formed at room temperature by addition of equal amount of starter culture in milk is maximum in the month of:
(1) February
(2) May
(3) August
(4) November
Q93. An in vitro technique, making large amount of any DNA sequence without the need for cloning is called the
(1) DNA sequencing
(2) Southern
(3) Polymerase chain reaction
(4) DNA fingerprinting.
Q94. A chemical substance that is produced in highest amount in nature is
(1) Chlorophyll
(2) Lignin
(3) Cellulose
(4) Pectin
Q95. Which of the following host defenses is considered a specific defense?
(1) Lysozyme in tears
(2) Low pH in stomach
(3) Secretion of mucus
(4) Production of antibodies by lymphocytes
Q96. A single bacterial cell is allowed to reproduce in liquid culture under favorable conditions. During which period will the total number of living cells be decreasing?
(1) The beginning of lag phase
(2) The middle of log phase
(3) The middle of the death phase
(4) The middle of the stationary phase.
Q97. The death curve when microbes are exposed to adverse conditions during sterilization represents
(1) A straight line
(2) Parabolic curve
(3) Hyperbolic curve
(4) Sigmoid curve
Q98. Which of the following is not a step of downstream processing:
(1) Precipitation
(2) Mutation
(3) Crystallization.
(4) Filtration
Q99. An organism responsible for spoilage of canned food is:
(1) Xanthomonas
(2) Pseudomonas
(3) Methanomonas
(4) Clostridium.
Q100.Chemically viruses are:
(1) Proteins
(3) Glycoproteins
(2) Phospholipids
(4) Nucleoproteins.
