What is the role played by non-pathogenic bacteria?

Q. What is the role played by non-pathogenic bacteria?
  1 They cause diseases
  2 They do not cause diseases
  3 They are of no use
  4 They attack only plants
  Ans:2
Q. What is the bacterial disease in lime fruits?
  1 Phytophthora
  2 White rust
  3 Citrus canker
  4 Smut disease
  Ans:3
Q. The leaf blight of paddy is caused by
  1 Bacteria
  2 Virus
  3 Nematodes
  4 Fungus
  Ans:1
Q. Which of the following is a bacterial disease?
  1 Early blight of potatoes
  2 Loose smut of wheat
  3 Red rot of sugarcane
  4 Red stripe of sugarcane
  Ans:4
Q. The nucleus is absent in
  1 Algae
  2 Fungi
  3 Escherichia coli
  4 Angiosperm
  Ans:3
Q. Bacterial action changes dead leaves into:
  1 Algae
  2 Fungi
  3 Humus
  4 None of the above
  Ans:3
Q. A bacterium divides every minute and takes an hour to fill a cup. How much time will it take to fill half the cup?
  1 15 minutes
  2 30 minutes
  3 59 minutes
  4 60 minutes
  Ans:3
Q. The necrotic ring spot disease of stone fruits (cherry, peach, plum, etc.) is caused by
  1 A bacterium
  2 Fungal infection
  3 Molybdenum deficiency
  4 Virus
  Ans:4
Q. Which of the following disease is not caused by virus?
  1 Ranikhet
  2 Blu tongue
  3 Babesiosis
  4 Marek's disease
  Ans:3
Q. One Gigabyte is Approximately equal is
  1 1000,000 bytes
  2 1000,000,000 bytes
  3 1000,000,000,000 bytes
  4 None of these
  Ans:2