NEET Biology Microbes In Human Welfare MCQs Set B

Question: Trichoderma polysporum is a source of

• a) Cyclosporin-A
• b) Streptokinase
• c) Statins
• d) Clot buster

Answer: Cyclosporin-A

Question: Select the incorrect match

• a) Citric acid – Aspergillus flavus
• b) Clot buster – Streptococcus
• c) Cyclosporin A – Trichoderma
• d) Butyric acid – Clostridium butylicum

Answer: Citric acid – Aspergillus flavus

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

• a) Penicillin
• b) Streptomycin
• c) Aflatoxin
• d) Gluconic acid

Answer: Penicillin

Question: The greater BOD of waste water relates

• a) Decreases oxygen content of water
• b) All of these
• c) Decreases oxygen content of water
• d) The decrease of temperature of water

Answer: Decreases oxygen content of water

Question: Ganga Action Plan for controlling pollution in Ganges started in

• a) 1985
• b) 1981
• c) 1987
• d) 1989

Answer:  1985

Question:

• a) The greater the BOD of waste water, less is its polluting potential
• b) The BOD test is a measure of the organic matter present in the water
• c) 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
• d) Waste water is treated till BOD is reduced significantly

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

Question:  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

• a) All are correct
• b) (ii) and (iii) are correct
• c) (i) and (ii) are correct
• d) (i) and (iii) are correct

Answer: All are correct

Question: Secondary treatment of sewage

• a) Involves microbial digestion of organic matter
• b) Does not require aeration
• c) Involves shredding, churning, filtration and sedimentation
• d) Removes grit and large pieces of organic matter

Answer: Involves microbial digestion of organic matter

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

• a) Primary treatment
• b) Secondary treatment
• c) Tertiary treatment
• d) Biological treatment

Answer:  Primary treatment

Question: Biogas contains

• a) 50% – 70% Methane
• b) 30% – 40% Methane
• c) 50% – 70% CO₂
• d) 20% Methane

Answer: 50% – 70% Methane

Question: First step in biogas production is carried out with the help of

• a) Decomposers
• b) Obligate aerobes
• c) Methanogens
• d) Parasites

Answer: Decomposers

Question: Identify the incorrect statement w.r.t. biogas plant

• a) A floating cover is placed over the slurry, which keeps on rising as the gas is consumed in the tank
• b) It has an outlet, which is connected to pipe to supply biogas to nearby houses
• c) The spent slurry is removed and may be used as fertiliser
• d) It consists of a concrete tank, 10-15 feet deep in which bio-wastes are collected and a slurry of dung is fed

Answer: A floating cover is placed over the slurry, which keeps on rising as the gas is consumed in the tank

Question: Identify the incorrect statement w.r.t. biogas plant

• a) A floating cover is placed over the slurry, which keeps on rising as the gas is consumed in the tank
• b) It has an outlet, which is connected to pipe to supply biogas to nearby houses
• c) The spent slurry is removed and may be used as fertiliser
• d) It consists of a concrete tank, 10-15 feet deep in which bio-wastes are collected and a slurry of dung is fed

Answer: A floating cover is placed over the slurry, which keeps on rising as the gas is consumed in the tank

Question: Find the correct option (w.r.t. Bioherbicide)

• a) More than one option is correct
• b) Helianthus annus
• c) Cactoblastis cactorum
• d) Phytophthora palmivora

Answer: More than one option is correct

Question: Which of the following is included in biopesticide?

• a) Viruses, bacteria, fungi and protozoa
• b) Viruses and bacteria only
• c) Viruses, bacteria and fungi only
• d) Viruses, bacteria, fungi and protozoa only

Answer: Viruses, bacteria, fungi and protozoa

Question: Baculoviruses are/have

• a) Pathogens that attack insects and other arthropods
• b) Members of genus Nucleopolyhedrovirus that are never used as biocontrol
• c) Species-specific, broad spectrum insecticides
• d) Few negative impacts on plants, mammals, birds, fishes or even on non-target insects

Answer: Pathogens that attack insects and other arthropods

Question: 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 introducedinto plants

• a) (i) and (iii)
• b) (ii) and (iv)
• c) (ii) and (iii)
• d) (i) and (ii)

Answer: (i) and (iii)

Question: Which of the following are natural insecticides?

(a) Rotenone (b) Pyrethrum
(c) Nicotine (d) Azadirachtin

• a) (a), (b), (c) & (d)
• b) (a) & (b) only
• c) (a), (c) & (d) only
• d) (a), (b) & (c) only

Answer: (a), (b), (c) & (d)

Question: Biofertilisers include

• a) Blue-green algae, Rhizobium, other nitrogen-fixing bacteria and mycorrhiza
• b) Blue-green algae, Trichoderma, Rhizobium and other nitrogen-fixing bacteria
• c) Rhizobium, other nitrogen-fixing bacteria, NPV and mycorrhiza
• d) Blue-green algae, Rhizobium, Bt and mycorrhiza

Answer: Blue-green algae, Rhizobium, other nitrogen-fixing bacteria and mycorrhiza

Question: Which of the following is not a symbiotic nitrogen fixing bacterium?

• a) Clostridium
• b) Frankia
• c) Rhizobium leguminosarum
• d) Mycobacterium

Answer: Clostridium

Question: Which of the following is not the belief of an organic farmer?

• a) For controlling plant diseases and pests, chemicals like insecticides and pesticides should be used extensively
• b) Eradication of the pests is undesirable because they act as food or hosts for beneficial predatory and parasitic insects
• c) 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
• d) The more variety a landscape has, the more sustainable it is

Answer: For controlling plant diseases and pests, chemicals like insecticides and pesticides should be used extensively

More Questions.....................................

Question: Organisms called Methanogens are most abundant in a

• a) Cattle yard
• b) Polluted stream
• c) Sulphur rock
• d) Hot spring

Answer: Cattle yard

Question: Secondary sewage treatment is mainly a

• a) Biological process
• b) Physical process
• c) Mechanical process
• d) Chemical process

Answer: Biological process

Question: Which of the following is mainly produced by the activity of anaerobic bacteria on sewage ?

• a) Marsh gas
• b) Laughing gas
• c) Propane
• d) Mustard gas

Answer: Marsh gas

Question: Continuous addition of sugars in 'fed batch' fermentation is done to

• a) Purify enzymes
• b) Obtain antibiotics
• c) Produce methane
• d) Degrade sewage

Answer: Purify enzymes

Question: Ethanol is commercially produced through a particular species of

• a) Saccharomyces
• b) Clostridium
• c) Aspergillus
• d) Trichoderma

Answer: Saccharomyces

Question: The most common substrate used in distilleries for the production of ethanol is

• a) Molasses
• b) Corn meal
• c) Soya meal
• d) Ground gram

Answer: Molasses

Question: Which one of the following is not a biofertilizer ?

• a) Agrobacterium
• b) Rhizobium
• c) Nostoc
• d) Mycorrhiza

Answer: Agrobacterium

Question: An organism used as a biofertilizer for raising soyabean crop is

• a) Rhizobium
• b) Azospirillum
• c) Azotobacter
• d) Nostoc

Answer: Rhizobium

Question: 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 ?

• a) (B) and (C) only
• b) (A) and (B) only
• c) (B), (C) and (D)
• d) (C) and (D) only

Answer: (B) and (C) only

Question: Select the correct statement from the following

• a) Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria
• b) Biogas is produced by the activity of aerobic bacteria on animal waste
• c) Methanobacterium is an aerobic bacterium found in rumen of cattle
• d) Biogas, commonly called gobar gas, is pure methane

Answer: Activated sludge-sediment in settlement tanks of sewage treatment plant is a rich source of aerobic bacteria

Question: An example of endomycorrhiza is

• a) Glomus
• b) Nostoc
• c) Agaricus
• d) Rhizobium

Answer: Glomus

Question: A common biocontrol agent for the control of plant diseases is

• a) Trichoderma
• b) Baculovirus
• c) Bacillus thuringiensis
• d) Glomus

Answer: Trichoderma

Question: Which one of the following is not used in organic farming?

• a) Snail
• b) Glomus
• c) Earthworm
• d) Oscillatoria

Answer: Snail

Question: Which of the following is not used as a biopesticide?

• a) Xanthomonas campestris
• b) Trichoderma harzianum
• c) Nuclear Polyhedrosis Virus (NPV)
• d) Bacillus thuringiensis

Answer: Xanthomonas campestris

Question: Which one of the following proved effective for biological control of nematodal disease in plants?

• a) Pseudomonas cepacia
• b) Pisolithus tinctorius
• c) Gliocladium virens
• d) Pseudomonas cepacia

Answer: Pseudomonas cepacia

Question: Modern detergents contain enzyme preparations of

• a) Acidophiles
• b) Thermophiles
• c) Alkaliphiles
• d) Thermoacidophiles

Answer: Acidophiles

Question: Trichoderma harzianum has proved a useful microorganism for

• a) Biological control of soil-borne plant pathogens
• b) Reclamation of wastelands
• c) Bioremediation of contaminated soils
• d) Gene transfer in higher plants

Answer: Biological control of soil-borne plant pathogens

Question: Probiotics are

• a) Live microbial food supplement
• b) Safe antibiotics
• c) New kind of food allergens
• d) Cancer inducing microbes

Answer: Live microbial food supplement

Question: Which one of the following pairs is wrongly matched?

• a) Coliforms – Vinegar
• b) Yeast – Ethanol
• c) Methanogens – Gobar gas
• d)  Streptomycetes – Antibiotic

Answer: Coliforms – Vinegar

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

• a) Bio-insecticidal plants
• b) Bio-metallurgical technique
• c) Bio-mineralization processes
• d) Bio-fertilizers

Answer: Bio-insecticidal plants

Question: A good producer of citric acid is

• a) Aspergillus
• b) Saccharomyces
• c) Clostridium
• d) Pseudomonas

Answer: Aspergillus

Question: Which one of the following pairs is wrongly matched?

• a) Alcohol - nitrogenase
• b) Textile - amylase
• c) Detergents - lipase
• d) Fruit juice - pectinase

Answer: Alcohol - nitrogenase

Question: Gobar gas contains mainly

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which bacteria is utilized in gober gas plant?

• a) Methanogens
• b) Nitrifying bacteria
• c) Denitrifying bacteria
• d) Ammonifying bacteria

Answer: Methanogens

Question: During anaerobic digestion of organic waste, such as in producing biogas, which one of the following is left undegraded ?

• a) Lignin
• b) Hemi-cellulose
• c) Cellulose
• d) Lipids

Answer: Lignin

Question: A major component of gobar gas is

• a) Methane
• b) Ethane
• c) Butane
• d) Ammonia

Answer:  Methane

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

• a) Bt-cotton to increase cotton yield
• b) Lady bird beetle against aphids in mustard
• c) Trichoderma sp. against certain plant pathogens
• d) Nucleopolyhedrovirus against white rust in Brassica

Answer: Bt-cotton to increase cotton yield

Question: One of the major difficulties in the biological control of insect/pest is that

• a) The predator does not always survive when transferred to a new environment
• b) The predator develops a preference to other diets and may itself become a pest
• c) The predator develops a preference to other diets and may itself become a pest
• d) None of these

Answer: The predator does not always survive when transferred to a new environment

Question: Cochineal insects have proved very useful for the control of

• a) Cactus
• b) Eicchornia
• c) Weeds
• d) Parthenium

Answer: Cactus

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

• a) Biological control
• b) Artificial control
• c) Confusion technique
• d) Genetic engineering

Answer: Biological control

Question: Which of the following is not used as a biopesticide?

• a) Xanthomonas campestris
• b) Trichoderma harzianum
• c) Bacillus thuringiensis
• d) Nuclear Polyhedrosis Virus (NPV)

Answer: Xanthomonas campestris

Question:  A common biocontrol agent for the control of plant diseases is

• a) Trichoderma
• b) Bacillus thuringiensis
• c) Baculovirus
• d) Glomus

Answer:  Trichoderma

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

• a) Azolla pinnata
• b) Legume-Rhizobium symbiosis
• c) Cyanobacteria
• d) Mycorrhiza

Answer: Azolla pinnata

Question:  Which one of the following helps in absorption of phosphorus from soil by plants?

• a) Glomus
• b) Anabaena
• c) Rhizobium
• d) Frankia

Answer: Glomus

Question:  Which of the following fern is an excellent biofertilizer?

• a) Azolla
• b) Pteridium
• c) Marsilea
• d) Salvinia

Answer: Azolla

Question:  Due to which of the following organism, yield of rice is increased?

• a) Anabaena
• b) Bacillus subtilis
• c) Bacillus popilliae
• d) Sesbania

Answer: Anabaena

Question:  The biofertilizers are

• a) Anabaena and Azolla
• b) Quick growing crop ploughed under soil
• c) Cow dung, manure and farmyard waste
• d) None of these

Answer: Anabaena and Azolla

Question:   Which of the following species does not have the ability to fix atmospheric nitrogen?

• a) Spirogyra
• b) Nostoc
• c) Anabaena
• d) Azotobactor

Answer: Spirogyra

Question: Due to which of the following organism, yield of rice is increased?

• a) Anabaena
• b) Bacillus subtilis
• c) Bacillus popilliae
• d) Sesbania

Answer: Anabaena

Question: Which of the following is a symbiotic nitrogen fixer?

• a) Frankia
• b) Azotobacter
• c) Glomus
• d) Azolla

Answer: Frankia

Question:  An alga which can be employed as food for human being is

• a) Chlorella
• b) Ulothrix
• c) Spirogyra
• d) Polysiphonia

Answer: Chlorella