The growth curve of bacterial population in lab is plotted agains

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 Multiple Choice QuestionsMultiple Choice Questions

161.

Select the correct pair of microorganism and the product obtained from it.

  • Monascus purpureus- produces large holes in Swiss cheese.

  • Saccharomyces cerevisiae - used for making wine and beer after distillation

  • Streptococcus - produces streptokinase which is used to remove clots.

  • Aspergillus niger - produces citric acid and butyric acid.


162.

Assertion: While working on Staphylococci, Alexander Fleming observed that Penicillin nolatum inhibits the growth of the bacteria.

Reason : This inhibiting chemical was commercially extracted and its full potential was established by Alexander Fleming.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are hue but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.


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163.

The growth curve of bacterial population in lab is plotted against time. What will be the shape of graph

  • Sigmoid

  • Hyperbolic

  • Ascending straight line

  • Descending straight line


B.

Hyperbolic

Under continuous supply of food and spacein the laboratory conditions the bacterial population grows exponentially and shows a Jshaped curve, thus the curve would be hyperbolic.

Such populations ultimately crash when the population size grows beyond carrying capacity.


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164.

Pollution from animal excreta and organic waste from kitchen can be most profitably minimized by

  • storing them in underground storage tanks

  • using them for producing biogas

  • vermiculture

  • using them directly as biofertilizers


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165.

Continued consumption of a diet rich in butter, red meat and eggs for a long period may lead to:

  • vitamin toxicity

  • kidney stones

  • hypercholesterolemia

  • urine laden with ketone bodies


166.

Latest trend in plant disease control is

  • chemical control

  • biological control

  • good manure and fertilizer

  • breeding for disease resistance


167.

Assertion : Yeasts such as Saccharomyces cerevisiae are used in baking industry.

Reason : Carbon dioxide produced during fermentation causes bread dough to rise by thermal expansion.

  • If both Assertion and Reason are true and the reason is the correct explanation of the assertion

  • If both Assertion and Reason are true but the reason is not the correct explanation of the assertion

  • If Assertion is true statement but Reason is false

  • If both Assertion and Reason are false statements


168.

One of the major difficulties in the biological control of insect pests is the :

  • practical difficulty of introducing the predator to specific areas

  • method is less effective as compared with the use of insecticides

  • predator does not always survive when transferred to a new environment

  • predator develops a preference to other diets and may itself become a pest


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169.

Creosote is used to prevent:

  • rusts of wheat

  • dry rot of wood

  • loose smut of oats

  • brown rust of barley


170.

Which of the following insecticide is obtained from the roots of Derris elliptica ?

  • Cinerin

  • Nicotine

  • Rotenone

  • Pyrethrum


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