In This Post we are  providing Chapter-10 Microbes in Human Welfare NCERT MCQ for Class 12 Biology which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS  can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.

NCERT MCQ ON MICROBES IN HUMAN WELFARE

Question 1 :  The primary treatment of waste water involves the removal of

• a) stable particles
• b) toxic substances
• c) harmful bacteria
• d) dissolved impurities

Answer :  stable particles

Question 2:  BOD of waste water is estimated by measuring the amount of

• a) oxygen consumption
• b) oxygen evolution
• c) biodegradable organic matter
• d) total organic matter

Answer :  oxygen consumption

Question 3:  Which one of the following alcoholic drinks is produced without distillation?

• a) Wine
• b) Whisky
• c) Rum
• d) Brandy

Answer :  Wine

Question 4 :  Which of these processes does not give off CO₂?

• a) Lactate fermentation
• b) Aerobic respiration
• c) Alcoholic fermentation
• d) None of these

Answer :  Lactate fermentation

Question 5 :  High biological oxygen demand in a water body means

• a) Water is polluted
• b) Water is not polluted
• c) Waterbody contains lots of lifeforms
• d) None of these

Answer :  Water is polluted

Question 6:  The guts of various ruminants contain

• a) Methanogens
• b) Halophiles
• c) Broth
• d) None of these

Answer :  Methanogens 

Question 7 : Conversion of sugar into alcohol during fermentation is due to the direct action of

a) temperature
b) micro-organisms
c) zymase
d) concentration of sugar solution

Answer : C

Question 8: Glucose fermentation by yeast yields

a) ethanol + CO₂   b) ethanol + H₂O
c) methanol + CO₂ d) H₂O + CO₂

Answer : A

Question 9: Streptokinase, used as a ‘clot buster’ is obtained from

a) Streptococcus b) Staphylococcus
c) Lactobacillus    d) Saccharomyces

Answer : A

Question 10 : Cyclosporin A is used for

a) dissolving blood clots
b) lowering cholesterol level
c) immunosuppression
d) enhancing tenderness of meat

Answer : C

Question 11 : The bioactive molecule Cyclosporin A is used in the treatment of

a) whooping cough b) diphtheria
c) leprosy                d) organ-transplant patients

Answer : D

Question 12: Statins are obtained from

a) Streptococcus           b) Mucor javanicus
c) Monascus purpureus d) Clostridium butyricum

Answer : C

Question 13: Statins, a bioactive molecule, inhibits the enzyme responsible for synthesis of

a) carbohydrate b) protein
c) vitamins         d) cholesterol

Answer : D

Question 14 : Monascus purpureus is a yeast used commercially in the production of

a) ethanol
b) streptokinase for removing clots from the blood vessels
c) citric acid
d) blood cholesterol lowering statins

Answer : D

Question 15 : The large vessels for growing microbes on an industrial scale are called _________ .

a) Petridis        b) digestors
c) biogas vessel d) fermenter

Answer : D