Microbes in Human Welfare - 1 File Download...Dosa and idli are fermentated by Leuconostoc and Streptococcus species of bacteria. 5. Read the following four statements (A – D) about

Level - II

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Solutions

SECTION - A

Objective Type Questions

(Introduction)

1. Identify the colonies labelled as A and B.

(A) (B)

(1) A-Fungal; B-Bacterial (2) A-Bacterial; B-Fungal

(3) A-Algal; B-Viral (4) A-Fungal; B-Algal

Sol. Answer (2)

In figures A – Bacterial colony

B – Fungal culture

2. Match the following (column-I with column-II)

Column I Column II

a. (i) Bacillus

b. (ii) Cocci

Chapter 6

Microbes in Human Welfare

52 Microbes in Human Welfare Solutions of Assignment (Level-II)

Aakash Educational Services Limited - Regd. Office : Aakash Tower, 8, Pusa Road, New Delhi-110005 Ph.011-47623456

c. (iii) Tobacco Mosaic

Virus (TMV)

d. (iv) Adenovirus

(1) a(iii), b(iv), c(i), d(ii) (2) a(iv), b(iii), c(i), d(ii)

(3) a(iii), b(i), c(iv), d(ii) (4) a(i), b(iii), c(ii), d(iv)

Sol. Answer (2)

In given figures:

a – Adenovirus

b – TMV

c – Bacillus

d – Cocci

(Microbes in Household Products)

3. The fermented food of soyabean is

(1) Tempeh (2) Tofu (3) Sufu (4) All of these

Sol. Answer (4)

Soyabean + H2O Soya souce

Food

obtain

Tempeh - Indonesia

Tofu - Japanese

Sufu - Chinese

4. Dosa and idli are fermented preparation of rice and black gram. The fermentation is done with

(1) Leuconostoc (2) Streptococcus

(3) Saccharomyces (4) More than one option is correct

Sol. Answer (4)

Dosa and idli are fermentated by Leuconostoc and Streptococcus species of bacteria.

5. Read the following four statements (A – D) about certain mistakes in two of them :

(A) Dough, which is used for making foods such as dosa and idli is fermented by fungi and algae

(B) Toddy, a traditional drink of southern India is made by fermenting sap from palms.

(C) Large hole in 'Swiss cheese' are due to production of large amount of methane by Propionibacterium

sharmanii

(D) In our stomach, lactic acid bacteria play very beneficial role in checking disease - causing microbes

Which are the two statements having mistakes ?

(1) Statements (A) & (C) (2) Statements (A) & (B)

(3) Statements (B) & (C) (4) Statements (C) & (D)

Sol. Answer (1)

(A) Dough is used for making dosa and idli and is fermented by bacteria

(C) Large hole in 'Swiss cheese' are due to production of CO2 by Propionibacterium sharmanii

53Solutions of Assignment (Level-II) Microbes in Human Welfare


(Microbes in Industrial Products)

6. Fermented beverage with maximum alcohol content is

(1) Beer (2) Brandy (3) Whisky (4) Gin

Sol. Answer (2)

Beer – 3-6% alcohol content

Whisky – 50% alcohol content

Brandy – 60-70% alcohol content

Gin – 40% alcohol content

7. Brewer’s yeast is used for ___A___ of malted cereals and fruit juices to produce ___B___.

(1) A - Distillation; B - CO2

(2) A - Distillation; B - organic acid

(3) A - Fermentation; B - CO (4) A - Fermentation; B - Alcohol

Sol. Answer (4)

Brewer's yeast is used for fermentation of malted cereals and fruit juices to produce alcohol.

8. Identify the correct statements w.r.t. antibiotics

(i) Fleming, Chain and Florey were awarded the Nobel prize in 1945

(ii) Antibiotics have greatly improved our capacity to treat deadly diseases

(iii) Penicillin was used to treat American soldiers wounded in World War I

(1) (i) and (ii) (2) (i) and (iii) (3) (ii) and (iii) (4) All are correct

Sol. Answer (1)

Correct statement are (i) and (ii)

Penicillin was used to treat American soldiers wounded in World War II.

9. __A__ enzyme is used to remove clots from the blood vessels of patients who have undergone __B__ leading

to heart attack.

(1) A-Streptokinase; B-Myocardial infarction (2) A-Lipases; B-Arteriosclerosis

(3) A-Proteases; B-Myocardial infarction (4) A-Pectinases; B-Atherosclerosis

Sol. Answer (1)

A-Streptokinase; B-Myocardial infarction

10. The bottled juices are clarified by the use of

(1) Pectinases (2) Proteases (3) Lipases (4) Both (1) & (2)

Sol. Answer (4)

Pectinase – Aspergillus niger and Byssochlamys fulva

Protease – Mortirella renispora, Aspergillus and Bacillus species

11. Trichoderma polysporum is a source of

(1) Cyclosporin-A (2) Streptokinase (3) Statins (4) Clot buster

Sol. Answer (1)

Trichoderma polysporum – Cyclosporin A

Streptococcus – Clot buster

Monascus purpureus – Statins

Streptococcus – Streptokinase



12. Select the incorrect match

(1) Citric acid – Aspergillus flavus

(2) Clot buster – Streptococcus

(3) Cyclosporin A – Trichoderma

(4) Butyric acid – Clostridium butylicum

Sol. Answer (1)

Citric acid – Aspergillus niger

Afflatoxin – Aspergillus flavus

13. Which fungal extract was extensively used in treating wounded American soldiers in world war-II?

(1) Streptomycin (2) Penicillin (3) Aflatoxin (4) Gluconic acid

Sol. Answer (2)

Penicillin is obtained from Penicillium notatum fungus.

(Microbes in Sewage Treatment)

14. The greater BOD of waste water relates

(1) Increases oxygen content of water (2) Decreases oxygen content of water

(3) The decrease of temperature of water (4) All of these

Sol. Answer (2)

The greater BOD of waste water indicates decrease in oxygen content of water.

15. Ganga Action Plan for controlling pollution in Ganges started in

(1) 1985 (2) 1981 (3) 1987 (4) 1989

Sol. Answer (1)

Ganga Action Plan for controlling pollution in Ganga, was started in 1985.

16. All are correct w.r.t. BOD (Biochemical Oxygen Demand), except

(1) It refers to the amount of oxygen that would be consumed if all the organic matter in one liter of water were

oxidised by bacteria

(2) The BOD test is a measure of the organic matter present in the water

(3) The greater the BOD of waste water, less is its polluting potential

(4) Waste water is treated till BOD is reduced significantly

Sol. Answer (3)

Greater the BOD of waste water greater is its polluting potential because higher BOD indicates large amount

of organic matter.

17. The Ministry of Environment and Forest has initiated Ganga action plan and Yamuna action plan

(i) To save these major rivers of our country from pollution

(ii) It is proposed to build a large number of sewage treatment plants

(iii) Under these plans, only treated sewage may be discharged in the river

(1) (i) and (ii) are correct (2) (ii) and (iii) are correct

(3) (i) and (iii) are correct (4) All are correct

Sol. Answer (4)

The ministry of environment and forest has initiated Ganga Action Plan and Yamuna Action Plan.



18. Secondary treatment of sewage

(1) Removes grit and large pieces of organic matter

(2) Involves shredding, churning, filtration and sedimentation

(3) Does not require aeration

(4) Involves microbial digestion of organic matter

Sol. Answer (4)

Secondary treatment of sewage involves microbial digestion of organic matter.

19. The removal of floating and suspended solids from sewage through filtration and sedimentation is the part of

(1) Primary treatment (2) Secondary treatment

(3) Tertiary treatment (4) Biological treatment

Sol. Answer (1)

The removal of floating and suspended solids from sewage through filtration and sedimentation is the part of

primary treatment of sewage.

(Microbes in Production of Biogas)

20. Biogas contains

(1) 30% – 40% Methane (2) 50% – 70% CO2

(3) 50% – 70% Methane (4) 20% Methane

Sol. Answer (3)

Biogas contains

CH4 – 50-70%

CO2 – 30-40%

H2, H

2S etc – 10%

21. First step in biogas production is carried out with the help of

(1) Obligate aerobes (2) Decomposers

(3) Methanogens (4) Parasites

Sol. Answer (2)

First step in biogas production is carried out with the help of decomposers i.e., Methanogens which are

anaerobic bacteria.

22. Identify the incorrect statement w.r.t. biogas plant

(1) It consists of a concrete tank, 10-15 feet deep in which bio-wastes are collected and a slurry of dung is fed

(2) A floating cover is placed over the slurry, which keeps on rising as the gas is consumed in the tank

(3) It has an outlet, which is connected to pipe to supply biogas to nearby houses

(4) The spent slurry is removed and may be used as fertiliser

Sol. Answer (2)

A floating covers is placed over slurry which keeps on rising as the gas is produced in the tank due to microbial

activity.



23. Which of the following statement for sewage is correct?

(1) Municipal waste-water, whose major component is human excreta

(2) Contains large amount of organic matter and non-pathogenic microbes

(3) Can be discharged directly into natural water bodies like rivers and streams

(4) It is generated in less quantities in cities and villages as compared to towns

Sol. Answer (1)

Sewage is municipal waste water, having major component as human excreta.

(Biocontrol Agents)

24. Find the correct option (w.r.t. Bioherbicide)

(1) Cactoblastis cactorum (2) Helianthus annus

(3) Phytophthora palmivora (4) More than one option is correct

Sol. Answer (4)

Bioherbicides

Cactoblastis cactorum (Cochineal insect) control prickly pear cactus

Phytophthora palmivora (Devine) control milkweed vines in citrus orchards

25. Which of the following is included in biopesticide?

(1) Viruses and bacteria only (2) Viruses, bacteria and fungi only

(3) Viruses, bacteria, fungi and protozoa (4) Viruses, bacteria, fungi and protozoa only

Sol. Answer (3)

Biopesticides – Virus, bacteria, fungi & protozoa

Baculovirus Bacillusthuringiensis

Trichoderma

26. Baculoviruses are/have

(1) Pathogens that attack insects and other arthropods

(2) Members of genus Nucleopolyhedrovirus that are never used as biocontrol

(3) Species-specific, broad spectrum insecticides

(4) Few negative impacts on plants, mammals, birds, fishes or even on non-target insects

Sol. Answer (1)

Pathogens that attack insects and other arthropods. The baculoviruses are family of large rod-shaped circular

DNA viruses that can be divided to two genera- nucleopolyhedroviruses (NPV) and granuloviruses (GV)

27. Identify the incorrect statement.

(i) Bacillus thuringiensis are available in sachets as dried spores which are mixed with kerosine and sprayed

on to vulnerable plants

(ii) B. thuringiensis are used to control butterfly caterpillars, but leave other insects unharmed

(iii) The toxin of B. thuringiensis is released in the blood of larvae and the larvae get killed

(iv) By the development of methods of genetic engineering B. thuringiensis toxin genes have been introduced

into plants

(1) (i) and (ii) (2) (ii) and (iii) (3) (i) and (iii) (4) (ii) and (iv)



Sol. Answer (3)

(i) Dried spores are mixed with H2O

(ii) Toxin of Bacillus thuringiensis is released in the gut of larvae and the larvae get killed.

28. Which of the following are natural insecticides?

(a) Rotenone

(b) Pyrethrum

(c) Nicotine

(d) Azadirachtin

(1) (a), (b) & (c) only (2) (a), (c) & (d) only (3) (a) & (b) only (4) (a), (b), (c) & (d)

Sol. Answer (4)

All are natural insecticides.

29. Mark the mismatched pair:

(1) Dragonfly – Biocontrol agent (2) Oscillatoria – Increase alkalinity of soil

(3) Anaerobic sludge digester – Biogas (4) VAM – Biofertiliser

Sol. Answer (2)

Oscillatoria decreases alkalinity of soil called reclamation of soil.

(Microbes as Biofertilisers)

30. Biofertilisers include

(1) Blue-green algae, Rhizobium, other nitrogen-fixing bacteria and mycorrhiza

(2) Blue-green algae, Trichoderma, Rhizobium and other nitrogen-fixing bacteria

(3) Rhizobium, other nitrogen-fixing bacteria, NPV and mycorrhiza

(4) Blue-green algae, Rhizobium, Bt and mycorrhiza

Sol. Answer (1)

Biofertilisers include blue-green algae, Rhizobium, other nitrogen-fixing bacteria and mycorrhiza.

31. Which of the following is not a symbiotic nitrogen fixing bacterium?

(1) Clostridium (2) Rhizobium leguminosarum

(3) Frankia (4) Mycobacterium

Sol. Answer (1)

Clostridium is free-living anaerobic nitrogen-fixing bacterium.

32. Which of the following is not the belief of an organic farmer?

(1) The more variety a landscape has, the more sustainable it is

(2) The insects that are sometimes called pests are not eradicated, but instead are kept at manageable levels by

a complex system of checks and balances within a living and vibrant ecosystem

(3) For controlling plant diseases and pests, chemicals like insecticides and pesticides should be used extensively

(4) Eradication of the pests is undesirable because they act as food or hosts for beneficial predatory and parasitic

insects

Sol. Answer (3)

The organic farmers do not use insecticides and pesticides chemicals.



33. The symbiotic association of fungi with plants is known as ____which is formed by many members of the fungal

genus_____.

(1) Mycorrhiza; Glomus (2) Mycorrhiza; Penicillium

(3) Lichen; Trebauxia (4) Lichen; Rhizocarpon

Sol. Answer (1)

Mycorrhiza; Glomus (Fungus).

34. Consider the following four statements (A - D) related to organic farming and select the correct option stating

which ones are true (T) and which ones are false (F). The statements :

(A) Produces food crops rich in lipids, vitamins and iron

(B) Uses biofertilisers which increases soil fertility

(C) There is more use of chemical fertilisers and pesticides

(D) Raising unpolluted crops through the use of bacteria, fungi and cyanobacteria

(A) (B) (C) (D)

(1) T T F F

(2) F T F T

(3) T F T F

(4) T F F F

Sol. Answer (2)

Organic farming produces crops rich in proteins.

35. Concept of sustainable agriculture lies in

(1) Minimizing biopesticides

(2) A greater dependance on new crops

(3) Least use of biofertilizers

(4) Using spores of Bacillus thuringiensis for pest control

Sol. Answer (4)

Concept of sustainable agriculture lies in using spores of Bacillus thuringiensis for pest control.

36. Indian curd is prepared by inoculating cream and skimmed milk with

(1) Lactobacillus acidophilus

(2) Leuconostoc cremoris

(3) Lactobacillus bulgaricus

(4) Streptococcus lactis

Sol. Answer (1)

37. Biogas production is a

(1) Three step microbial process

(2) Three step physical process

(3) Four step aerobic process

(4) Four step anaerobic process

Sol. Answer (1)



38. The first antibiotic was discovered accidently by __A__ while working on __B__.

(1) A-Waksman; B-Streptococcus (2) A-Fleming; B-Penicillium notatum

(3) A-Waksman; B-Bacillus brevis (4) A-Fleming; B-Staphylococci

Sol. Answer (4)

The first antibiotic was discovered accidently by Fleming while working on Staphylococcus.

SECTION - B

Previous Years Questions

1. Which of the following is a commercial blood cholesterol lowering agent? [NEET-2019]

(1) Cyclosporin A (2) Statin (3) Streptokinase (4) Lipases

Sol. Answer (2)

Statin is obtained from a yeast (Fungi) called Monascus purpureus

It acts by competitively inhibiting the enzyme responsible for synthesis of cholesterol.

2. Select the correct group of biocontrol agents. [NEET-2019]

(1) Bacillus thuringiensis, Tobacco mosaic virus, Aphids

(2) Trichoderma, Baculovirus, Bacillus thuringiensis

(3) Oscillatoria, Rhizobium, Trichoderma

(4) Nostoc, Azospirillium, Nucleopolyhedrovirus

Sol. Answer (2)

Fungs Trichoderma, Baculoviruses (NPV) and Bacillus thuringiensis are used as biocontrol agents.

Rhizobium, Nostoc, Azospirillum and Oscillatoria are used as biofertilisers, whereas TMV is a pathogen and

aphids are pests that harm crop plants.

3. Match the following organisms with the products they produce [NEET-2019]

(a) Lactobacillus (i) Cheese

(b) Saccharomyces (ii) Curd

cerevisiae

(c) Aspergillus niger (iii) Citric Acid

(d) Acetobacter aceti (iv) Bread

(v) Acetic Acid

Select the correct option.

(a) (b) (c) (d)

(1) (ii) (iv) (v) (iii)

(2) (ii) (iv) (iii) (v)

(3) (iii) (iv) (v) (i)

(4) (ii) (i) (iii) (v)

Sol. Answer (2)

Microbes are used in production of several household and industrial products –

Lactobacillus – Production of curd

Saccharomyces cerevisiae – Bread making

Aspergillus niger – Citric acid production

Acetobacter aceti – Acetic acid



4. Which of the following can be used as a biocontrol agent in the treatment of plant disease? [NEET-2019]

(1) Trichoderma (2) Chlorella

(3) Anabaena (4) Lactobacillus

Sol. Answer (1)

Fungus Trichoderma is a biological control agent being developed for use in the treatment of plant diseases.

5. Conversion of milk to curd improves its nutritional value by increasing the amount of [NEET-2018]

(1) Vitamin D (2) Vitamin A

(3) Vitamin E (4) Vitamin B12

Sol. Answer (4)

Curd is more nourishing than milk.

It contains number of vitamins specially Vit-B12

.

6. Which of the following in sewage treatment removes suspended solids? [NEET-2017]

(1) Tertiary treatment (2) Secondary treatment

(3) Primary treatment (4) Sludge treatment

Sol. Answer (3)

Primary treatment is a physical process which involves sequential filtration and sedimentation.

7. Which of the following is correctly matched for the product produced by them? [NEET-2017]

(1) Acetobacter aceti : Antibiotics

(2) Methanobacterium : Lactic acid

(3) Penicillium notatum : Acetic acid

(4) Saccharomyces cerevisiae : Ethanol

Sol. Answer (4)

Saccharomyces cerevisiae is commonly called Brewer’s yeast. It causes fermentation of carbohydrates

producing ethanol.

8. Select the mismatch [NEET-2017]

(1) Frankia – Alnus

(2) Rhodospirillum – Mycorrhiza

(3) Anabaena – Nitrogen fixer

(4) Rhizobium – Alfalfa

Sol. Answer (2)

Rhodospirillum is anaerobic, free living nitrogen fixer.

Mycorrhiza is a symbiotic relationship between fungi and roots of higher plants.

9. Match Column-I with Column-II and select the correct option using the codes given below :

Column-I Column-II

a. Citric acid (i) Trichoderma

b. Cyclosporin A (ii) Clostridium

c. Statins (iii) Aspergillus

d. Butyric acid (iv) Monascus



Codes : [NEET(Phase-2)-2016]

a b c d

(1) (iii) (i) (ii) (iv)

(2) (iii) (i) (iv) (ii)

(3) (i) (iv) (ii) (iii)

(4) (iii) (iv) (i) (ii)

Sol. Answer (2)

Microbe Product

Aspergillus niger - Citric acid

Trichoderma polysporum - Cyclosporin-A

Monascus purpureus - Statins

Clostridium butylicum - Butyric acid

10. Which of the following is wrongly matched in the given table? [NEET-2016]

Clostridiumbutylicum

Microbe

Trichodermapolysporum

Monascuspurpureus

Streptococcus

Lipase

Product

Cyclosporin A

Statins

Streptokinase

removal of oil stains

Application

immunosuppressivedrug

lowering of blood cholesterol

removal of clot from blood vessel

(1)

(2)

(3)

(4)

Sol. Answer (1)

Butyric acid is produced by fermentive activity of Clostridium butylicum.

11. Match the following list of microbes and their importance: [Re- AIPMT-2015]

a. Saccharomyces cerevisiae (i) Production of immunosuppressive agents

b. Monascus purpureus (ii) Ripening of Swiss cheese

c. Trichoderma polysporum (iii) Commercial production of ethanol

d. Propionibacterium sharmanii (iv) Production of blood-cholesterol lowering agents

(1) a(iii), b(i), c(iv), d(ii) (2) a(iii), b(iv), c(i), d(ii) (3) a(iv), b(iii), c(ii), d(i) (4) a(iv), b(ii), c(i), d(iii)

Sol. Answer (2)

Microbes Importance

(a) Sacharomyces cerevisiae – Commercial production of ethanol.

(b) Monascus purpureus – Production of blood cholesterol lowering agents

(c) Trichoderma polysporum – Production of immunosuppressive agents

(d) Propionibacterium sharmanii – Ripening of Swiss cheese

12. What gases are produced in anaerobic sludge digesters? [AIPMT-2014]

(1) Methane and CO2 only (2) Methane, Hydrogen sulphide and CO

2

(3) Methane, Hydrogen sulphide and O2

(4) Hydrogen sulphide and CO2



Sol. Answer (2)

In anaerobic sludge digesters, bacteria produce a mixture of gases like CH4, H

2S and CO

2.

13. Besides paddy fields, cyanobacteria are also found inside vegetative part of [NEET-2013]

(1) Cycas (2) Equisetum (3) Psilotum (4) Pinus

Sol. Answer (1)

BGA are also found in coralloid roots of Cycas for nitrogen-fixation e.g. Nostoc & Anabaena.

14. A good producer of citric acid is [NEET-2013]

(1) Pseudomonas (2) Clostridium (3) Saccharomyces (4) Aspergillus

Sol. Answer (4)

Citric acid – Aspergillus niger.

15. During sewage treatment, biogases are produced which include : [NEET-2013]

(1) Methane, oxygen, hydrogen sulphide (2) Hydrogen sulphide, methane, sulphur dioxide

(3) Hydrogen sulphide, nitrogen, methane (4) Methane, hydrogen sulphide, carbon dioxide

Sol. Answer (4)

Biogas – Methane (CH4), hydrogen sulphide (H

2S), carbon dioxide (CO

2).

16. The domestic sewage in large cities [AIPMT (Mains)-2012]

(1) Has a high BOD as it containing both aerobic and anaerobic bacteria

(2) Is processed by aerobic and then anaerobic bacteria in the secondary treatment in Sewage Treatment

Plants (STPs)

(3) When treated in STPs does not really require the aeration step as the sewage contains adequate

oxygen

(4) Has very high amounts of suspended solids and dissolved salts

Sol. Answer (2)

17. Monascus purpureus is a yeast used commercially in the production of [AIPMT(Prelims)-2012]

(1) Blood cholesterol lowering statins

(2) Ethanol

(3) Streptokinase for removing clots from the blood vessels

(4) Citric acid

Sol. Answer (1)

Monascus perpureus is a yeast commercially used in production of blood cholesterol lowering statins.

18. In Gobar gas, the maximum amount is that of [AIPMT (Mains)-2012]

(1) Butane (2) Methane (3) Propane (4) Carbon dioxide

Sol. Answer (2)

In gobar gas, maximum amount is of Methane (CH4).

19. Yeast is used in the production of [AIPMT (Prelims)-2012]

(1) Bread and beer (2) Cheese and butter

(3) Citric acid and lactic acid (4) Lipase and pectinase



Sol. Answer (1)

Yeast – Saccharomyces cerevisiae used in production of bread and beer.

20. A nitrogen fixing microbe associated with Azolla in rice fields is [AIPMT (Prelims)-2012]

(1) Frankia (2) Tolypothrix (3) Spirulina (4) Anabaena

Sol. Answer (4)

Anabaena azollae associated with Azolla (fern).

21. Measuring Biochemical Oxygen Demand (BOD) is a method used for [AIPMT (Prelims)-2012]

(1) Measuring the activity of Saccharomyces cervisae in producing curd on a commercial scale

(2) Working out the efficiency of R.B.Cs. about their capacity to carry oxygen

(3) Estimating the amount of organic matter in sewage water

(4) Working out the efficiency of oil driven automobile engines

Sol. Answer (3)

Measuring Biochemical Oxygen Demand (BOD) is a method used for estimating the amount of organic matter

present in sewage water.

22. The most abundant prokaryotes helpful to humans in making curd from milk and in production of antibiotics

are the ones categorised as [AIPMT (Prelims)-2012]

(1) Chemosynthetic autotrophs (2) Heterotrophic bacteria

(3) Cyanobacteria (4) Archaebacteria

Sol. Answer (2)

23. Which one of the following is a wrong matching of a microbe and its industrial product, while the remaining

three are correct? [AIPMT (Mains)-2012]

(1) Clostridium butylicum - lactic acid (2) Aspergillus niger - citric acid

(3) Yeast - statins (4) Acetobacter aceti - acetic acid

Sol. Answer (1)

Clostridium butylicum - Butyric acid.

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

[AIPMT (Prelims)-2012]

(1) Bt-cotton to increase cotton yield (2) Lady bird beetle against aphids in mustard

(3) Trichoderma sp. against certain plant pathogens (4) Nucleopolyhedrovirus agains white rust in Brassica

Sol. Answer (1)

25. Which one of the following microbes forms symbiotic association with plants and helps them in their nutrition?


(1) Glomus (2) Trichoderma (3) Azotobacter (4) Aspergillus

Sol. Answer (1)

Glomus fungus.

26. Organisms called Methanogens are most abundant in a [AIPMT (Prelims)-2011]

(1) Hot spring (2) Sulphur rock (3) Cattle yard (4) Polluted stream

Sol. Answer (3)



27. Secondary sewage treatment is mainly a [AIPMT (Prelims)-2011]

(1) Biological process (2) Physical process (3) Mechanical process (4) Chemical process

Sol. Answer (1)

Secondary sewage treatment is mainly a biological process.

28. Which of the following is mainly produced by the activity of anaerobic bacteria on sewage?


(1) Marsh gas (2) Laughing gas (3) Propane (4) Mustard gas

Sol. Answer (1)

29. Ethanol is commercially produced through a particular species of [AIPMT (Prelims)-2011]

(1) Aspergillus (2) Saccharomyces (3) Clostridium (4) Trichoderma

Sol. Answer (2)

Ethanol is commercially produced through Saccharomyces.

30. The most common substrate used in distilleries for the production of ethanol is [AIPMT (Prelims)-2011]

(1) Molasses (2) Corn meal (3) Soya meal (4) Ground gram

Sol. Answer (1)

The most common substrate used in distilleries for the production of ethanol is molasses.

31. Which one of the following is not a biofertilizer? [AIPMT (Prelims)-2011]

(1) Mycorrhiza (2) Agrobacterium (3) Rhizobium (4) Nostoc

Sol. Answer (2)

Agrobacterium is used in genetic engineerring.

32. An organism used as a biofertilizer for raising soyabean crop is [AIPMT (Prelims)-2011]

(1) Nostoc (2) Azotobacter (3) Azospirillum (4) Rhizobium

Sol. Answer (4)

Rhizobium leguminosarum is gram negative bacteria which fix - nitrogen as symbiosis in leguminous crops

e.g. soyabean.

33. Consider the following statements (A-D) about organic farming

A. Utilizes genetically modified crops like Bt cotton.

B. Uses only naturally produced inputs like compost.

C. Does not use pesticides and urea.

D. Produces vegetables rich in vitamins and minerals.

Which of the above statements are correct ? [AIPMT (Mains)-2011]

(1) (B) and (C) only (2) (A) and (B) only

(3) (B), (C) and (D) (4) (C) and (D) only

Sol. Answer (1)

Organic farming uses only naturally produced inputs like compost. It does not use pesticides and urea.



34. Select the correct statement from the following [AIPMT (Prelims)-2010]

(1) Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic

bacteria

(2) Biogas is produced by the activity of aerobic bacteria on animal waste

(3) Methanobacterium is an aerobic bacterium found in rumen of cattle

(4) Biogas, commonly called gobar gas, is pure methane

Sol. Answer (1)

Activated sludge sediments in settling tanks of sewage treatment plant is rich source of aerobic bacteria.

35. An example of endomycorrhiza is [AIPMT (Mains)-2010]

(1) Nostoc (2) Glomus (3) Agaricus (4) Rhizobium

Sol. Answer (2)

36. A common biocontrol agent for the control of plant diseases is [AIPMT (Prelims)-2010]

(1) Trichoderma (2) Baculovirus

(3) Bacillus thuringiensis (4) Glomus

Sol. Answer (1)

37. Which one of the following is not used in organic farming? [AIPMT (Prelims)-2010]

(1) Snail (2) Glomus (3) Earthworm (4) Oscillatoria

Sol. Answer (1)

Glomus and Oscillatoria Biofertilisers

Earthworm Detrivores

38. Which of the following is not used as a biopesticide? [AIPMT (Prelims)-2009]

(1) Trichoderma harzianum (2) Nuclear Polyhedrosis Virus (NPV)

(3) Xanthomonas campestris (4) Bacillus thuringiensis

Sol. Answer (3)

39. Which one of the following proved effective for biological control of nematodal disease in plants?


(1) Paecilomyces lilacinus (2) Pisolithus tinctorius

(3) Pseudomonas cepacia (4) Gliocladium virens

Sol. Answer (3)

Pseudomonas cepacia – Biological control of nematodal disease.

40. Modern detergents contain enzyme preparations of [AIPMT (Prelims)-2008]

(1) Thermophiles (2) Acidophiles (3) Alkaliphiles (4) Thermoacidophiles

Sol. Answer (2)

Modern detergents contain enzyme preparations of acidophiles.



41. Trichoderma harzianum has proved a useful microorganism for [AIPMT (Prelims)-2008]

(1) Biological control of soil-borne plant pathogens (2) Bioremediation of contaminated soils

(3) Reclamation of wastelands (4) Gene transfer in higher plants

Sol. Answer (1)

Trichoderma harzianum has proved a useful micro-organism for Biological control of soil-borne plant pathogens.

42. Probiotics are [AIPMT (Prelims)-2007]

(1) Live microbial food supplement (2) Safe antibiotics

(3) Cancer inducing microbes (4) New kind of food allergens

Sol. Answer (1)

43. Which one of the following pairs is wrongly matched? [AIPMT (Prelims)-2007]

(1) Coliforms – Vinegar (2) Methanogens – Gobar gas

(3) Yeast – Ethanol (4) Streptomycetes – Antibiotic

Sol. Answer (1)

44. Bacillus thuringiensis (Bt) strains have been used for designing novel [AIPMT (Prelims)-2005]

(1) Bio-metallurgical technique (2) Bio-mineralization processes

(3) Bio-insecticidal plants (4) Bio-fertilizers

Sol. Answer (3)

45. A good producer of citric acid is

(1) Pseudomonas (2) Clostridium (3) Saccharomyces (4) Aspergillus

Sol. Answer (4)

46. Which one of the following pairs is wrongly matched?

(1) Textile - amylase (2) Detergents - lipase

(3) Alcohol - nitrogenase (4) Fruit juice - pectinase

Sol. Answer (3)

Alcohol - zymase.

47. Gobar gas contains mainly

(1) CO2 + H

2(2) CO

2 + H

2O (3) CH

4 only (4) CH

4 + CO

2

Sol. Answer (4)

Gobar gas CH4 + CO

2+ H

2S

48. Which bacteria is utilized in gober gas plant?

(1) Methanogens (2) Nitrifying bacteria

(3) Ammonifying bacteria (4) Denitrifying bacteria

Sol. Answer (1)

Methanogens bacteria



49. During anaerobic digestion of organic waste, such as in producing biogas, which one of the following is left

undegraded?

(1) Lipids (2) Lignin

(3) Hemi-cellulose (4) Cellulose

Sol. Answer (2)

During anaerobic digestion of organic waste, such as in producing biogas, lignin remains undegraded.

50. A major component of gobar gas is

(1) Ammonia (2) Methane

(3) Ethane (4) Butane

Sol. Answer (2)

Major component of gobar gas is Methane (CH4).

51. Microbe used for biocontrol of pest butterfly caterpillars is

(1) Trichoderma sp. (2) Saccharomyces cerevisiae

(3) Bacillus thuringiensis (4) Streptococcus sp.

Sol. Answer (3)

Microbe used for biocontrol of pest butterfly catterpillars is - Bacillus thuringiensis.

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

(1) Bt-cotton to increase cotton yield

(2) Lady bird beetle against aphids in mustard

(3) Trichoderma sp. against certain plant pathogens

(4) Nucleopolyhedrovirus against white rust in Brassica

Sol. Answer (1)

Biological control of pests/diseases using microbes is Bt-cotton to increase cotton yield.

53. One of the major difficulties in the biological control of insect/pest is that

(1) The method is less effective as compared with the use of insecticides

(2) The practical difficulty of introducing the predator to specific areas

(3) The predator develops a preference to other diets and may itself become a pest

(4) The predator does not always survive when transferred to a new environment

Sol. Answer (4)

Major difficulties in biological control of insects/pests is the predator does not always survive when transferred

to a new environment.

54. Cochineal insects have proved very useful for the control of

(1) Cactus (2) Eicchornia (3) Weeds (4) Parthenium

Sol. Answer (1)

Cochineal insect (Cactoblastic cactorum) have proved very useful for the control of cactus.



55. When a natural predator (living being) is applied on the other pathogen organism to control them, this process

is called

(1) Artificial control (2) Confusion technique

(3) Biological control (4) Genetic engineering

Sol. Answer (3)

Biological control.

56. Farmers have reported over 50% higher yields of rice by using which of the following biofertilizer?

(1) Cyanobacteria (2) Legume-Rhizobium symbiosis

(3) Mycorrhiza (4) Azolla pinnata

Sol. Answer (4)

Azolla pinnata is biofertilizer.

57. Which one of the following helps in absorption of phosphorus from soil by plants?

(1) Anabaena (2) Glomus (3) Rhizobium (4) Frankia

Sol. Answer (2)

In mycorrhizal association fungus Glomus absorbs phosphorus from soil.

58. Which of the following fern is an excellent biofertilizer?

(1) Marsilea (2) Pteridium (3) Azolla (4) Salvinia

Sol. Answer (3)

Azolla is natural biofertilizers.

59. Due to which of the following organism, yield of rice is increased?

(1) Sesbania (2) Bacillus popilliae (3) Anabaena (4) Bacillus subtilis

Sol. Answer (3)

60. Which of the following species does not have the ability to fix atmospheric nitrogen?

(1) Azotobactor (2) Anabaena (3) Nostoc (4) Spirogyra

Sol. Answer (4)

Alga Spirogyra is not a nitrogen-fixer.

61. The biofertilizers are

(1) Anabaena and Azolla (2) Cow dung, manure and farmyard waste

(3) Quick growing crop ploughed under soil (4) None of these

Sol. Answer (1)

Anabaena and Azolla are biofertilizers.

62. Which of the following is a symbiotic nitrogen fixer?

(1) Azolla (2) Glomus (3) Azotobacter (4) Frankia

Sol. Answer (4)

Frankia is symbiotic nitrogen-fixer in non leguminous plant e.g. Alnus and Casuarina.



63. An alga which can be employed as food for human being is

(1) Ulothrix (2) Chlorella (3) Spirogyra (4) Polysiphonia

Sol. Answer (2)

Chlorella – SCP

SECTION - C

Assertion-Reason Type Questions

1. A : Curd is more nutritious than milk.

R : LAB present in curd checks growth of disease causing microbes.

Sol. Answer (2)

Curd is more nutritious than milk, in curd LAB are found. They check growth of disease causing microbes in

our stomach.

2. A : After 24 hours toddy becomes unpalatable.

R : Toddy left for a few hours undergoes fermentation.

Sol. Answer (1)

After 24 hours toddy becomes unpalatable because toddy left over a few hours undergoes fermentation.

3. A : Newer antibiotics are required to be produced regularly.

R : Pathogens often develop resistance to existing antibiotics.

Sol. Answer (1)

Pathogens often develop resistance to existing antibiotics so newer antibiotics are required to be produced

regularly.

4. A : Cyclosporin A is an immunosuppressive medicine.

R : It stimulates activation of T-cells and prevents rejections.

Sol. Answer (3)

Cyclosporin A is an immunosuppressive medicine, it prevents organ rejection.

5. A : Barley, Sorghum and millet are smoother crops.

R : They favour the growth of some common weeds.

Sol. Answer (3)

Barley, Sorghum and millet are smoother crops. They retard the growth of weeds.

6. A : Cheese is one of the oldest food items in which microbes are used.

R : Different varieties of cheese are known by characteristic texture, flavour and taste.

Sol. Answer (2)

Cheese is one of the oldest food items, prepared by use of various types of micro-organisms. Different varieties

of cheese are characterised w.r.t. texture, flavour and taste.

e.g., swiss cheese, roquefort cheese, camembert cheese.

7. A : Baculovirus are species specific.

R : It is very common in root ecosystem and effective against several plant pathogens.



Sol. Answer (3)

Baculovirus are species specific. It is a parasite of insects and other arthropods.

8. A : Statins are product of fermentation activity of yeast.

R : Statins and mevalonate compete for same active site on enzyme involved in cholesterol synthesis.

Sol. Answer (2)

Statins are produced by fermentation activity of yeast. Both statins and mevalonate compete for same active

site on enzyme that is involved in cholesterol synthesis.

9. A : Wine and beer are produced by distillation of the fermented broth.

R : Different types of alcoholic drinks are obtained only by fermentation, always followed by distillation process.

Sol. Answer (4)

Wine and beer are produced without distilation of fermented broth, so they have low concentration of alcohols.

Alcoholic drinks obtained by fermentation and followed by with or without distilation process.

10. A : The chief component of biogas is CH4.

R : Biogas plants are prepared on the foregin technology.

Sol. Answer (3)

The chief component of biogas is methane i.e., 50% - 70%. Biogas plants are prepared on the Indian

technology.

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Microbes in Human Welfare - 1 File Download...Dosa and idli are fermentated by Leuconostoc and Streptococcus species of bacteria. 5. Read the following four statements (A – D) about