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cbse 12th Standard Biology Microbes in Human Welfare Model Questions Papers Study Material - QB365

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Questions:

Multiple Choice Question

45 x 1 = 45

Given below are the list of the commercially important products and their source organisms. Select the option that gives the correct matches.

List A (Bioactive products)	List B Microbes (Source organism)
A. Cyclosporin A	1. Streptococcus
B. Statins	2. Tricoderma polysporum
C. Streptokinase	3. Penicillium notatum
D. Penicillin	4. Monascus purpureus

(a)

A-1, B-2, C-3, D-4

(b)

A-3, B-4, C-2, D-1

(c)

A-4, B-3, C-2, D-1

(d)

A-2, B-4, C-1, D-3

Bt crops are resistant to pests. Identify the bacterium from whom the gene is isolated for pest resistance.

(a)

Bacillus thuringiensis

(b)

Bacillus thermusaquaticus

(c)

Pseudomonas

(d)

Staphylococcus

Which one of the following statement regarding BOD is true?

(a)

The greater the BOD of waste, less is its polluting potential

(b)

The greater the BOD of wastewater, greater its polluting potential

(c)

The lesser the BOD of wastewater more is its polluting potential

(d)

All of the above

The technology of biogas production from cow dung was developed in India largely due to the efforts of

(a)

Gas Authority of India

(b)

Oil and Natural Gas Commission

(c)

Indian Agricultural Research Institute, Khadi and Village Industries Commission

(d)

Indian Oil Corporation

Match the following list of microbes and their importance.

Microorganisms	Importance
A. Saccharomyces	1. Production of immunosuppressive agents
B. Monascus	2. Ripening of Swiss cheese
C. Trichoderma polysporum	3. Commercial production of ethanol
D. Propionibacterium shermanii	4. Production of blood-cholesterol lowering agents

(a)

A-3, B-4, C-1, D-2

(b)

A-4, B-3, C-2, D-1

(c)

A-4, B-2, C-1, D-3

(d)

A-3, B-1, C-4, D-2

Modern detergents contain enzyme preparation of

(a)

Thermoacidophiles

(b)

Alkaliphiles

(c)

Thermophiles

(d)

Acidophiles

A patient brought to a hospital with myocardial infarction is normally immediately given

(a)

streptokinase

(b)

penicillin

(c)

cyclosporin-A

(d)

statins

Which one of the following antimicrobial drug is suitable for both leprosy and tuberculosis?

(a)

Isoniazid

(b)

R-aminosalicylic acid

(c)

Streptomycin

(d)

Rifampicin

Which is an incorrect statement about fermentation?

(a)

Toddy is prepared by fermenting palm sap

(b)

The Propionibacterium is used in fermentation of cheese

(c)

Fermentation in muscles produces alcohol

(d)

The production of CO₂ in dough causes puffed up appearance

10.

Cyanobacteria are used as biofertilisers because they

(a)

are photosynthetic

(b)

grow easily anywhere

(c)

have mucilage

(d)

fix atmospheric nitrogen

11.

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

(a)

Wine

(b)

Whisky

(c)

Rum

(d)

vitamin E.

12.

The vitamin whose content increases following the conversion of milk into curd by lactic acid bacteria

(a)

vitamin C

(b)

vitamin D

(c)

vitamin B₁₂

(d)

vitamin E.

13.

Propionibacterium produces large holes in swiss cheese due to the

(a)

process of oxidation of the dough

(b)

formation of large amount of CO₂

(c)

consumption of carbohydrates

(d)

all of these

14.

Lactic acid bacteria (LAB) grow in milk and convert it to curd and also improve its nutritional quality by increasing

(a)

vitamin A

(b)

vitamin B₁₂

(c)

vitamin B₆

(d)

vitamin C and A

15.

To speed up the malting process in brewing industry, the growth hormone used is

(a)

auxin

(b)

gibberellic acid

(c)

kinetin

(d)

ethylene

16.

Which one single organism or the pair of organisms is correctly assigned of its of their named taxonomic group

(a)

Paramecium and Plasmodium belong to the same kingdom as that of Penicillium

(b)

Lichen is a composite organism formed from the symbiotic association of an algae and a protozoan

(c)

yeast used in making bread and beer is a fungus

(d)

Nostoc and Anabaena are examples of protista

17.

Yeast is used in the production of

(a)

Citric acid lactic acid

(b)

Lipase and pecinase

(c)

Bread and beer

(d)

Cheese and butter

18.

Which one of the following is an example of carrying out biological control of pests/diseases using microbes?

(a)

Trichoderma sp. against certain plant pathogens

(b)

Nucleopolyhedrovirus against white rust in Brassica

(c)

Bt-cotton to increase cotton yield

(d)

Lady bird beetle against aphids in mustard

19.

Monasus 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

20.

Which one of the following is wrong matching of a microbe and its industrial product, while the remaining three are correct?

(a)

yeast - statins

(b)

Acetobacter aceti - acetic acid

(c)

Clostridium butylicum - lactic acid

(d)

Aspergillus niger - citric acid

21.

Match the items in column 'A' and column 'B' and choose correct answer

Column 'A'	Column 'B'
(i) Lady bird	(a) Methanobacterium
(ii) Mycorrhiza	(b) Trichoderma
(iii) Biological control	(c) Aphids
(iv) Bio-gas	(d) Glomus

(a)

(i)-(b), (ii)-(d), (iii)-(c), (iv)-(a)

(b)

(i)-(c), (ii)-(d), (iii)-(b), (iv)-(a)

(c)

(i)-(d), (ii)-(a), (iii)-(b), (iv)-(c)

(d)

(i)-(c), (ii)-(b), (iii)-(a), (iv)-(d)

22.

Activated sludge should have the ability to settle quickly so that it can

(a)

be rapidly pumped back from sedimentation to aeration tank

(b)

absorb pathogenic bacteria present in waste water while sinking to the bottom of the settling tank

(c)

be discarded and anaerobically digested

(d)

absorb colloidal organic matter

23.

Methanogens do not produce

(a)

oxygen

(b)

methane

(c)

hydrogen sulfide

(d)

carbon dioxide

24.

which one of the following is not a nitrogen-fixing organism?

(a)

Anabaena

(b)

Nostoc

(c)

Azotobacter

(d)

Pseudomonas

25.

Mycorrhiza does not help the host plant in:

(a)

Enhancing its phosphorus uptake capacity

(b)

Increasing its tolerance to drought

(c)

Enhancing its resistance to root pathogens

(d)

Increasing its resistance to insects

26.

Which of the following is dipteran?

(a)

Tobacco budworm

(b)

Armyworm

(c)

Beetle

(d)

Mosquito

27.

Which of the following is not concerned with biotechnology?

(a)

Biogas production

(b)

Sewage treatment

(c)

Biofertilizers

(d)

Wood seasoning

28.

Saccharomyces cerevisiae is used for production of

(a)

Bread

(b)

Ethanol

(c)

Both (a) and (b)

(d)

Acetic acid

29.

Which one of the following is not used as a biopesticide?

(a)

Trichoderma harzianum

(b)

Nuclear polyhedrosis virus (NPV)

(c)

Xanthomonas campestris

(d)

Bacillus thuringiensis

30.

Biochemical Oxygen demand (BOD) in a river water

(a)

has no relationship with concentration of oxygen in the water

(b)

gives a measure of Salmonella in the water

(c)

increases when sewage gets mixed with river water

(d)

remains unchanged when algal bloom occurs.

31.

Methanogens, growing anaerobically on cellulosic material, produce

(a)

Methane

(b)

Methane and carbon dioxide

(c)

Methane and hydrogen

(d)

Methane, carbon dioxide and hydrogen.

32.

Cyclosporin-A an immunosuppressive drug is produced by

(a)

Aspergillus niger

(b)

Manascus purpureus

(c)

Penicillium notatum

(d)

Trichoderma polysporum

33.

Which one of the following bacterium is used extensively as biopesticide?

(a)

Bacillus subtilis

(b)

Bacillus thuringiensis

(c)

Streptococcus lactis

(d)

Lactobacillus acidophilus

34.

Nigrogen fixation in root nodules of Alnus is brought about by

(a)

Frankia

(b)

Azorhizobium

(c)

Bradyrhizobium

(d)

Clostridium

35.

Which of the following is widely used as a successful biofertiliser in Indian rice field?

(a)

Rhizobium

(b)

Acacia arabica

(c)

Acalypha indica

(d)

Azolla pinnata

36.

Which of the following is maintained for optimum production of vinegar?

(a)

Anaerobic condition

(b)

Temperature of \(65^{ \circ }C\)

(c)

Aerobic condition

(d)

Microaerophilic condition

37.

Which of the following antibiotic is active against fungus?

(a)

Streptomycin

(b)

Polyenes

(c)

Tetracycline

(d)

Neomycin

38.

What happened when we inoculated Rhizobium in wheat field?

(a)

No increase in production (nitrogen content of soil remains same)

(b)

A lot of increase in production (nitrogen content of soil increases)

(c)

Fertility of soil decreases

(d)

Fertility of soil increases.

39.

A good example of organic fertilizer which improves phosphorus uptake is

(a)

Actinomycetes fungi

(b)

Rhizobium

(c)

Azospirillum

(d)

None of these

40.

Lactic acid is formed by the process of

(a)

Actinomycetes fungi

(b)

Rhizobium

(c)

Azospirillum

(d)

None of these

41.

In which one of the following the BOD (Bio-chemical Oxygen Demand) of Sewage (S), distillery effluent (DE), paper mill effluent (PE) and sugar mill effluent (SE) have been arranged in ascending order:

(a)

SE < PE < S < DE

(b)

PE < S < SE < DE

(c)

S < DE < PE < SE

(d)

SE < S < PE < DE

42.

Bio fertilisers include:

(a)

Blue-green algae, rhizobia, other nitrogen fixing bacteria and mycorrhiza fungi

(b)

Blue-green algae, rhizobia and other nitrogen fixings bacteria

(c)

Rhizobia, other nitrogen fixing bacteria and mycorrhiza fungi

(d)

Blue green algae, rhizobia and mycorrhiza fungi

43.

Bacillus thuringiensis (Bt) strains have been used for designing novel

(a)

Biofertilizers

(b)

Bio-metallurgical techniques

(c)

Bio-mineralization processes

(d)

Bio-insecticidal plants

44.

Which of the following can be controlled by using biopesticides?

(a)

Insects

(b)

Diseases

(c)

Weeds

(d)

All of them

45.

Which of the following is included in biopesticide?

(a)

Viruses and bacteria

(b)

Viruses, bacteria and fungi

(c)

Viruses, bacteria, fungi, protozoa and mites

(d)

Viruses, bacteria, fungi and protozoa

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Answers Key:

Multiple Choice Question

45 x 1 = 45

(d)
A-2, B-4, C-1, D-3

(a)
Bacillus thuringiensis

(b)
The greater the BOD of wastewater, greater its polluting potential

(a)
A-3, B-4, C-1, D-2

(b)
Alkaliphiles

(a)
streptokinase

(d)
Rifampicin

10.

(d)
fix atmospheric nitrogen

11.

(a)
Wine

12.

13.

(b)
formation of large amount of CO₂

14.

(b)
vitamin B₁₂

15.

(b)
gibberellic acid

16.

17.

18.

(a)
Trichoderma sp. against certain plant pathogens

19.

(d)
blood cholesterol lowering statins

20.

21.

(b)
(i)-(c), (ii)-(d), (iii)-(b), (iv)-(a)

22.

(a)
be rapidly pumped back from sedimentation to aeration tank

23.

(a)
oxygen

24.

(d)
Pseudomonas

25.

(d)
Increasing its resistance to insects

26.

(d)
Mosquito

27.

(d)
Wood seasoning

28.

(a)
Bread

29.

30.

31.

(d)
Methane, carbon dioxide and hydrogen.

32.

(d)
Trichoderma polysporum

33.

(b)
Bacillus thuringiensis

34.

(a)
Frankia

35.

(d)
Azolla pinnata

36.

(a)
Anaerobic condition

37.

(b)
Polyenes

38.

(a)
No increase in production (nitrogen content of soil remains same)

39.

40.

(a)
Actinomycetes fungi

41.

(b)
PE < S < SE < DE

42.

(a)
Blue-green algae, rhizobia, other nitrogen fixing bacteria and mycorrhiza fungi

43.

(d)
Bio-insecticidal plants

44.

(d)
All of them

45.

cbse 12th Standard Biology Microbes in Human Welfare Model Questions Papers Study Material - QB365 Set A

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Std: 12th Standard CBSE - Biology

chapter: Microbes in Human Welfare - Model Questions Papers

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