Agriculture Microbiology MCQ tribhuvan University 5

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