MCQ Agriculture Microbiology Tribhuvan university

MULTIPLE CHOICE QUESTIONS (MCQ)

Agriculture Microbiology
prepared by Tankeshwar Acharya

1.      Nitrification process is discovered by
a. Schloesing and Muntz (1877)                     b.Ruinen and Hiltner                
c. Winogradsky and Beijernickia                    d. Beijernickia and Winogradsky

2.      bacteria responsible for Nitrification is isolated by
a. Winogradsky b. Beijernickia          c. Ruinen          d. Hiltner

3.      The first member of the genus Azotobacter is discovered by………..
a. M.W. Beijerinck b. Winogradsky c. Ruinen            d. Hiltner

4.      The word Rhizosphere and Phyllosphere is respectively given by
A. Hiltner and  Ruinen                                    B.Ruinen and Hiltner    
C. Winogradsky and Beijernickia                   D. Beijernickia and Winogradsky

5.      the term Mycorrhiza is termed by
a. Ruinen       b. Hiltner          c. AB Frank (1885)d. Winogradsky

6.      Musty or Earthy odor of a freshly plowed field is due to
a. Nocardia   b. Streptomyces           c. Micromonospora      d. All    e. None

7.      Which of the following organism play a key role in the transformation of rock to soil.
a. Cyanobacteria   b. Bacillus spp      c. Pseudomonas spp     d. clostridium spp

8.      syntrophism is

a. relationship between two organisms where one organism benefits but the other is unaffected
b.  relationship in which two or more agents work together to produce a result not obtainable by any of the agents independently
c. symbiotic relationship between organisms in which one species is harmed or inhibited and the other species is unaffected
d. mutualistic association involving the exchange of nutrients between two species

9.      Winogradsky column is used
a. for isolation of purple and green phototrophic bacteria and other anaerobes
b. to measure the BOD
c. for the production of Sulphur
d. for the enumeration of Bacteria

10.  Which groups of the organisms are responsible for in the dissolution of rocks, especially those composed of limestone.
a. Chemoorganotrophs          b. Photoautotrophs       c. Photoorganotrophs             d. Chemoautotrophs     

11.  Dissolution of rocks is due to
a. Carbonic acid        b. Organic acid c. freezing and thawing  d. all of the above

12.   In which depth in a garden soil does the maximum number of microorganisms per gram occur?
a. at a depth of 3-8 cm. b. at a depth of 1-3 cm c. at a depth of 8-12 cm d. at a depth of 12-25 cm

13.  compound responsible for the distinctive “earthy” odor of soil is
a. Phytoalexins b. root exudates c. cellulose  d. Geosmin

14.  ………… is a common denitrifying bacteria?
a. Pseudomonas b. Nitrobacter c.frankia d. azospirillum

15.  dissimilatory sulfur- reducing bacteria……………
a. can reduce elemental sulfur to sulfide but are unable to reduce sulfate to sulfide
b. cant reduce elemental sulfur to sulfide but can reduce sulfate to sulfide
c. can reduce both elemental sulfur and sulfate to sulfide
d. cant reduce both elemental sulfur and sulfate

16.  Desulfuromonas is ………………..
a. obligate anaerobes b. sulfate reducing bacteria        c. both of above d. facultative aerobe

17.  Formation of “infection thread” in certain root hairs is due to
a. Rhizobium bacteria             b. pathogenic bacteria               c.

18.  Organisms involved in non symbiotic nitrogen fixations are the species of;
a. Spp of Azotobacter           b.Cyanobacteria           c. Clostridium             Pasteurianum d. all of the above

19.  The amount of nitrogen fixed by the non symbiotic process ranges between
a. 20-50lb/acre annually b 50-100 lb/ acre annually c. >200 lb/acre annually

20.  Nitrogenase enzyme complex contains component I an II……….
a. Nitrogenase and Nitrogenase reductase      b. MoFe protein and Fe protein
c. Both of the above                                      d. None of the above

21.  Widely used inexpensive technique to measure nitrogen fixation depends on
a. capability of nitrogen fixing enzyme (nitrogenase) to act upon acetylene.
b. Ninhydrin test
c. comparison of growth of plants in nitrogen supplemented and non supplemented fields.
d. direct measurement of fixed nitrogen from the soil

22.  bacteria of the both physiological groups, ammonia oxidizers and nitrite oxidizers are
a. Gram Negative Chemolithotrophs               b. both gram positive and gram negative Chemolithotrophs        c. Gram Negative Chemoorganotrophs  d. both gram negative and gram positive Chemoorganotrophs.

23.  Degradation of Lignin in forest soil constitutes the example of
a. Neutralism b. Mutalism      c. commensalisms         d. competition

24.  Ratio of the Microorganisms in the rhizoshphere compared to the microorganisms in the bulk soil i. e R:S ration typically ranges from
a. 2-5                        b. 5-10             c. 10-50           d.4-8

25.  Agricultural crops commonly contain ……………percentage of phosphorus in their tissue.
A. 0.05-0.5%                        B. 2.5-4%                    C. 2-3%                       D. 1-1.5%

26.  Fungal mycelium and Bacterial biomass contain…………….. percentage of Phosphorus respectively.
a. 0.5-1% and 1-3%             B.0.05-0.5% and 0.5-1%                                           C. 2% and 3%               D. 2.5-4% and 1.5-2.5%

27.  ………….. is called as Father of Soil Microbiology.
A. Hiltner      B  Ruinen         C Winogradsky            D. Beijernickia

28.  Nitrogen (N2) becomes a nitrate through the process of
A. Nitrification                       B. Nitrogen fixation                                                    C. Ammonification                    D. Denitrification

29.  Chemoautotrophy is discovered by,  
A. Hiltner      B  Ruinen         C Winogradsky            D. Beijernickia

30.  Nitrogen Fixing stage of rhizobium is called
a. Rhizoid      b. Bacteroid     c. Viroid           d. Bacteria

31.  which of the following is a strict anaerobic bacteria
a. pseudomonas spp  b. Bacillus         c. E. coli           d. Methanogenic bacteria

32.  if you want to remove high ammonium content for the river water, which one of the following bacterium will be useful
a. Rhizobium  b. E coli            c. Pseudomonas                       d. Nitrobacter

33.  Most efficient strains for the oxidation of ammonia to NO2 is
a. Nitrosococcus       b. Nitrospira     c. Nitrosomonas           d. Nitrosolobus

34.  which of the follwing two genera do not contain species that fix nitrogen symbiotically.
a. Rhizobium  b. Clostridium   c. Frankia         d. Anabaena    

35.  Desulphovibrio bacteria are found commonly in ponds;
a. surface of water     b. Middle zone c. bottom

36.  eutrophication of lakes lead to overgrowth of
a. grasses      b. algae and cyanobacteria        c. fungi d. none of the above

37.  phytoalexins are formed mostly in which part of plant
a. leaf                        b. fruit              c. root              d. flower

38.  which physical factor promote the microbial population in soil
a. sand                      b. clay              c. silt    d. Loam soil

39.  which of the following organism is cellulytic actinomycetes
a. Micromonas          b. Nocardia      c. Streptomyces            d. all of the above

40.  In the order of abundance which is the commonest genera of actinomyctes in soil.
a. Streptomyces         b. Nocardia      c. Micromonas             d. Actinoplanes

41.  The percentage of ……… in the total microbial population increases with the depth of soil.
a. Bacteria                 b. Virus            c. fungi             d. Actinomycetes

42.  ……………… are intolerant to acidity.
a. Bacteria                 b. Fungi            c. Actinomycetes          d. None

43.  Viruses do not attack
a. Bacteria                 b. Fungi            c. Actinomycetes          d. Attacks all

44.  Blue Baby Syndrome or Methemoglobinemia may be due to
a. Excessive Nitrates in drinking water
b. pyocyanin compound of Pseudomonas
c. sulfur contamination of water
d. both a and b

45.  Loam is a soil composed of
a. Sand, Silt and Clay in equal proportion       b. sand predominates c. clay predominates c the amount of sand and silt is equals to that of clay

46.  Bacteria responsible for denitrification are
a. Pseudomonas        b. Thiobacillus              c. Bacillus         d. All

47.  Nitrite oxidizing bacteria are
a. Nitrobacter            b. Nitrospina                c. Nitrococcus  d. All

48.  Ammonia oxidizing bacteria are
a. Nitrosomonas  b. Nirosococcus    c. Nirosolobus   d. Nitrosovibrio            e. All

49.  Nitrogen fixation by microorganisms is detected by
a. measuring the amount of nitrogen in soil      b. demonstration of growth in Nitrogen free medium c. rotation of the crops d. it is impossible to demonstrate

50.  Anaerobic Non symbiotic nitrogen fixing organism is/are
a. Clostridium pasteurianum   b. Azotobacter c. Both            d. None

51.  Moledenum metal is a component of enzyme complex and play a role in
a. Carbon cycle b. Nitrogen Fixation c. Sulphur oxidation       d. Denitrification

52.  leghemoglobin is
a. a type of hemoglobin responsible for carrying oxygen to tissues
b. red, iron containing protein, which has role in Nitrogen fixation
c. hemoglobin with sickle shape
d: hemoglobin responsible for phosphate solubilization

53.  rhizospheric effect is a type of ………… interaction
a. Neutralism             b. commensalisms         c. Synergism     d. Mutalism

54.  soil harbors, which one of the following pathogenic fungi
a. H. capsulatum        b. C. neoformans          c. A. fumigatus  d. all of the above

55.  microbial community in area of low PH is dominated by
a. Actinomycetes       b. Protozoa      c. Fungi            d. bacteria

56.  rhizobium and Azotobacter were discovered by
a. Beijernck   b. Winogradsky            c. Ruinen          d. Hiltner

57.  an obligate anaerobe, Clostridium pasteurianum, which is capable of fixing atomospheric nitrogen was identified by
a. Louis Pasteur         b. Beijernck      c. Winogradsky            d. Ruinen

58.  major inorganic sulfur compound in aerobic soil is ……………..
a. sulfite         b. sulfate           c. thiosulfate     d. Sulfide

59.  major inorganic sulfur compound in anaerobic soil is……….
a. sulfite         b. sulfate           c. thiosulfate     d. Sulfide

60.  the percentage of sulfur/phosphorus in the earths crust is
a. 0.1                        b. 0.2               c. 1      d. 3

61.  ………..percentage of plant material and ………….percentage of plant protein is composed of sulfur
a. 1,2                        b. 0.5 , 1          c. 2 , 3             d. 3 , 4.5

62.  lignin metabolism is triggered by……….
a. N, S, or C starvation          b.Supplement of N and C         c. addition of cellulose and hemicellulose                    d. supplement of C, N and S

63.  Lignin ………cellulose and hemicellulose decomposition.
a. Increases   b. decreases     c. acclerates     d.does not alter

64.  …….. of soil microbial population solubilizes phosphorus.
a. 10%          b. 20%             c 40%              d. 50%

65.  mechanism of phosphorus solubilization is by
a. chelation    b. iron reduction           c. acid production         d. all of the above

66.  in a food chain consisting of the following, which acts as the decomposer
a. Protozoa    b. Algae           c. helminth        d. fungi

67.  …………forms stem nodules.
a. Azorhizobium         b. Bradyrhizobium        c. Rhizobium     d. cyanobacteria

68.  ……..have been used for centuries to enrich ride paddies
a. Anabaena azollae   b. Frankia        c. Azospirillum lipoferum           d. rhizobium

69.  The size of the minerals clay, silt  and sand is respectively…………..
a. 2µm, 0.002-0.05 mm, 0.05-2.0 mm           b. 0.002-0.05 mm, 2µm, 0.05-2.0 mm
c. 0.05-2.0 mm, 2µm, ≥2.0 mm                     d. 2µm, 0.05-2.0 mm, 0.002-0.05mm

70.  which region of the soil profile is also called surface soil
a. C horizon   b. A horizon     c. O horizon     d. B horizon

71.  siderophores are
a. high affinity iron chelating compound           b. those which transport iron into bacterial cell               c. none          d. both

72.  application of the ammonium containing fertilizers………..
a. suppress the bacterial community    b. increases fungal population
c. both of the above                                       d. none of the above

73.  phyllospheric organisms does not take part in
a. mineralization         b. fertilizer effect           c. growth hormone production d. all

74.  heterocysts are
a. specialized nitrogen fixing cells        b. formed by cyanobacteria c. formed during nitrogen starvation            d. all of the above

75.  ….. soil is considered ideal for gardening and agricultural purposes.
a. loam soil    b. clay soil        c. sand soil       d. silt soil

76.  Azotobacter is
a. cyst forming bacteria          b. does not produce spores       c. strict aerobe 
d. all of the above

77.  diazotrophs are
a. organisms capable of nitrogen fixation b. organisms such as rhizobia, frankia, azospirillium c both of the above         d. none of the above

78.  which of the following horizon is dominant reservoir of Microbial food
a. A               b. B      c. C      d. O

79.  …………. Is also known as fat of the land.
a. clay soil     b. Humus          c. triglycerides              d. lignin

80.  Humus………….
a. consists of partially decomposed organic matter
b. dominant food reservoir
c. also called fat of the land
d. all of the above

81.  ……. Is a undesirable process form the standpoint of agriculture.
a. phosphorus solubilization                b. Denitrification           c. Nitrification
d. both a and b

82.  denitrification processes……………..
a. is an example of aerobic respiration            b. Remove nitrogen from soil
c. occurs when oxygen supply is abundant      d. all of the above

83.  nitrate and phosphate contamination of aquatic ecosystem causes
a. alagal bloom                      b. acclerated eutrophication
c. suffocation of aquatic aerobes        d. all of the above

84.  the order of soil population is
a. Bacteria >Actinomycetes >Fungi >Algae> Protozoa
b. Actinomycetes> Bacteria >Fungi>Protozoa> Algae
c. Bacteria> Protozoa> Fungi >Actinomycetes> Algae
d. Bacteria >Fungi >Actinomycetes> Algae >Protozoa

85.  Which one is responsible for denitrification
a. Nitrobacter            b. pseudomonas c. Bacillus       d. both b and c

86.  ……… make up a large percentage of rhizosphere than of the normal soil flora
a. Short gram negative rods    b. Gram positive rods   c. spore forming bacteria
d. Arthobacter group

87.  Species of Thiobacillus and Beggiatoa play an important role in the
a. Nitrogen cycle       b. Carbon cycle            c Phosphorus cycle       d. Sulfur cycle

88.  which of the following fungi oxidizes sulfur
a. Aspergillus b. Penicillum     c. both of above           d. none

89.  The PH range of thiobacilli is
a. 1.5-5         b. 1.5-8            c. 3-7               d. 2-5

90.  organic soil may contain bacteria up to …………. In significant number.
a. 10 cm        b. 20 cm           c. 160 cm         d. 40 cm

91.  lignin percentage of plant material is
a. 2-5%         b. 5-10% c. 15-25%    d. 5-30%

92.  in plant phosphorus is found in the form of
a. phytin        b. phosphorylated sugars          c. phospholipid   d. all of the above

93.  most common cellulose fermenter in nature are the member of ……..
a. clostridium b. azotobacter              c. Frankia         d. fusarium

94.  Normal C:N ration in humus is
a. 10:1           b.1:10              c 10:4               d. 10:3

95.  rice husk is least degradable type of solid waste because of
a. high C:N ratio        b. low C:N ratio           c. lack of water d. due to lignin

96.  the carbon and nitrogen content of humus is respectively
a. 60% ,3-6%           b. 40%, 5%      c. 20%, 1%      d. 15%, 25%

97.  Phytoalexins are
a. antimicrobial substances     b.synthesized denovo by the plants        c.both of the above d none

98.  which of the follwings are examples of mutalism……..
a. Lichens      b. Endosymbionts    c. Mycorrhizae      d. all of the above

99.  ……is a bacteria which is a parasite of other bacteria
a. bdevellovibrio        b. Rickesttsiae  c. Bateriophage           d. Viruses

100.                which organism prefer dry condition
a. Actinomycetes       b. fungi c. bacteria        d. protozoa