Biofertilizers And Antibiotics Test

Biofertilizers And Antibiotics

This is online test 01 for CBSE class 12 Biology Microbes in Human Welfare (Biofertilizers and antibiotics).. There are 10 questions in this test with each question having around four answer choices.

Questions & Answers

1
The chemical substances produced by some microbes and can kill or retard the growth of disease causing microbes are called
  • A
    All of these
  • B
    Antibodies
  • C
    Antibiotics
    Correct
  • D
    Antigens
2
Use of biocontrol measures will greatly reduce our dependence on
  • A
    Fertilizers and manure
  • B
    Useful chemicals and pesticides
  • C
    Plants and insects
  • D
    Toxic chemicals and pesticides
    Correct
3
Which of the following is a gram-negative bacterium?
  • A
    Streptomyces coelicolor
  • B
    Bacillus subtilis
  • C
    Escherichia coli
    Correct
  • D
    Amycolatopsis orientali
4
The common nitrogen-fixer in paddy fields is
  • A
    Frankia
  • B
    Azospirillum
    Correct
  • C
    Oscillatoria
  • D
    Rhizobium
5
The most important of the symbiotic nitrogen fixing bacteria which forms nodules on the roots of legume plants is
  • A
    Penicillium
  • B
    Rhizobium
    Correct
  • C
    Aspergillus
  • D
    Streptococcus
6
The term antibiotic was coined by
  • A
    Selman Waksman
    Correct
  • B
    Howard Florey
  • C
    Gerhard Domagk
  • D
    John Tyndall
7
Which of the following organisms not fix atmospheric nitrogen
  • A
    Spirogyra
    Correct
  • B
    Anabaena
  • C
    Oscillatoria
  • D
    Nostoc
8
Cyanobacteria serves as important biofertilizers in the fields of
  • A
    Rice
    Correct
  • B
    Sugarcane
  • C
    Maize
  • D
    Wheat
9
Fleming, Chain and Florey were awarded the Nobel Prize in 1945 for discovery of
  • A
    Antibiotic
    Correct
  • B
    None of these
  • C
    Insulin
  • D
    Antibodies
10
A nitrogen fixing microbe associated with Azolla in rice fields is
  • A
    Tolypothrix
  • B
    Anabaena
    Correct
  • C
    Spirulina
  • D
    Frankia