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Biology (NCERT) - Class XII > XII Chap 10 Microbes > Flashcards

XII Chap 10 Microbes Flashcards

1
Q

Microbes can exist in temperatures as high as 100°C or highly acidic environments. T or F?

A

True

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2
Q

Protozoa, bacteria, fungi, microscopic animal/plant viruses, viroids and prions are all _________

A

Microbes

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3
Q

Microbes like ______ and ______ can be grown on nutritive media to form colonies that can be seen with naked eye

A

fungi and bacteria

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4
Q

______ virus causes respiratory infections

A

Adenovirus

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5
Q

Tobacco mosaic virus is ___-shaped

A

Rod

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6
Q

Are all microbes harmful / pathogenic?

A

No

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7
Q

_________ grows in milk and converts it to curd. Describe the process.

A

Lactobacillus / lactic acid bacteria (LAB);

produce acids that coagulate and partially digest milk proteins

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8
Q

What is another name for starter?

A

inoculum

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9
Q

LAB increases nutritional quality in curd by increasing ____

A

Vitamin B12

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10
Q

LAB play a beneficial role in checking disease-causing microbes in the stomach. True or False?

A

True

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11
Q

Dough like dosa and idli is fermented by ______

A

bacteria

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12
Q

Puffed-up appearance of idli/dosa dough is due to ______

A

CO2 produced by bacteria

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13
Q

Bread is fermented by _____________

A

Saccharomyces cerevisiae (baker’s yeast aka brewer’s yeast)

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14
Q

Toddy is made by ______________

A

fermenting sap from palms

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15
Q

______ is one of the oldest foods in which microbes were used

A

Cheese

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16
Q

Large holes in ‘Swiss cheese’ is due to ________

A

large amount of CO2 produced by bacterium Propionibacterium sharmanii

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17
Q

Roquefort cheese are ripened by ________ which also give them a particular flavor

A

fungi

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18
Q

What are fermentors?

A

Very large vessels
Grow microbes
Industrial scale production

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19
Q

Malted cereals and fruit juices are fermented beverages formed using?

A

Saccharomyces cerevisiae (brewer’s yeast)

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20
Q

Saccharomyces cerevisiae produces ______ in the process of fermenting beverages

A

ethanol

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21
Q

Two types of processing in fermented beverages?

A 
With distillation of fermented broth (whisky, brandy and rum)
Without distillation (wine and beer)
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22
Q

Meaning of ‘anti’ ‘biotic’

A

Against life (i.e. against disease causing organisms)

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23
Q

______________ was the first antibiotic to be discovered

A

Penicillin

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24
Q

Who discovered Penicillin and how?

A

Alexander Fleming, observed a mould growing around which Staphylococci bacteria could not grow;

full potential discovered by Ernest Chain and Howard Florey

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25
Q

What was Penicillin used for when first discovered?

A

treat American soldiers wounded in World War II

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26
Q

___________ were awarded the Nobel Prize for discovering Penicillin

A

Fleming, Chain and Florey (1945)

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27
Q

What are some diseases that antibiotics have helped treat?

A

Plague,
Whooping cough (kaali khansi),
diphtheria (gal ghotu),
leprosy (kusht rog)

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28
Q

What microbes produce acids?

A 
Aspergillus niger (fungus) -> citric acid
Acetobacter aceti (bacterium) -> acetic acid
Clostridium butylicum (bacterium) -> butyric acid
Lactobacillus (bacterium) -> lactic acid
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29
Q

________ is used for commercial production of ethanol

A

Saccharomyces cerevisiae (yeast)

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30
Q

What are some examples of enzymes made by microbes? And their uses?

A

Lipase => detergent formulations, oily stains
Pectinase => clarify bottled juices
Protease => clarify bottled juices
Streptokinase => removing clots from blood vessels of patients who have undergone myocardial infarction leading to heart attack
Amylase => textiles

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31
Q

Streptokinase is produced by _________

A

bacterium Streptococcus

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32
Q

Cyclosporin A is used as _________ and Statins is used for ________

A

an immunosuppressive agent in organ transplants;

lowering blood cholesterol

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33
Q

Cyclosporin A is produced by ___________

A

fungus, Trichoderma polysporum

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34
Q

________ produced by _______ are used by blood-cholesterol lowering agents

A

Statins produced by yeast (FUNGUS) (Monascus purpureus)

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35
Q

How do statins act as blood-cholesterol lowering agents?

A

By inhibiting the enzyme responsible for synthesis of cholesterol (competitive inhibition in cholesterol synthesis pathway)

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36
Q

Treatment of waste water is done by _____________ microbes

A

heterotrophic

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37
Q

What are the 2 stages of sewage treatment?

A
  1. Primary treatment - physical removal of particles

2. Secondary treatment - reducing the BOD in the effluent

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38
Q

What happens in primary treatment of sewage?

A
  1. floating debris removed by sequential filtration
  2. grit (soil and small pebbles) removed by sedimentation

solids that settle => primary sludge
supernatant => effluent

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39
Q

What happens in secondary treatment of sewage?

A
  1. effluent passed into large aeration tanks -> agitated mechanically & air pumped into it
  2. vigorous growth of flocs (bacteria + fungi) => consume organic matter => BOD decreases
  3. effluent passed into settling tank => flocs sediment => activated sludge, some is used as inoculum and rest digested into biogas
  4. effluent released into natural water
40
Q

What is another name for secondary treatment of sewage?

A

Biological treatment

41
Q

What are flocs?

A

useful aerobic microbes
masses of bacteria + fungal filaments
mesh-like structures

42
Q

What is BOD?

A

Biochemical oxygen demand;

amount of oxygen that would be consumed if all the organic matter in one liter of water were oxidised by bacteria

43
Q

What does BOD test measure for?

A

rate of uptake of oxygen by micro-organisms;

indirect measure of the organic matter present in water

44
Q

The greater the BOD the lesser the pollution potential. T or F?

A

False, greater BOD => greater pollution potential

45
Q

What is activated sludge?

A

bacterial ‘flocs’ that sediment

46
Q

Activated sludge is pumped back into the aeration tank to serve as the ________

47
Q

What happens in anaerobic sludge digesters?

A

Majority of the activated sludge is pumped into these digesters where bacteria that grow anaerobically digest the bacteria+fungi in the sludge;
produces methane, hydrogen sulphide and carbon dioxide => biogas => inflammable

48
Q

What are methanogens?

A

Bacteria - grow anaerobically on cellulosic material - produce methane + CO2 + H2

e.g. Methanobacterium

49
Q

Where are methanogens commonly found?

A 
in anaerobic sludge during sewage treatment; 
in rumen (stomach) of cattle - help breakdown cellulose => also present in excreta (dung)
50
Q

Describe biogas plant

A

concrete tank (10-15 feet deep) => bio-waste collected + slurry of dung => floating cover that rises as gas produced => outlet for gas => spent slurry removed, used as fertiliser

51
Q

Biogas plants are more often built in _____ areas where biogas is used for ___ and _____

A

rural areas;

cooking & lighting

52
Q

Technology of biogas was developed in India mainly due to efforts of ____ and _____

A

IARI - Indian Agricultural Research Institute

KVIC - Khadi and Village Industries Commission

53
Q

What is biocontrol?

A

Biological method for controlling plant diseases / pests;
natural predation;
pests - manageable levels, not fully eradicated

54
Q

Examples of biocontrol agents

A

Ladybird - aphids
Dragonflies - mosquitos
Bacillus thuringiensis (Bt) - butterfly caterpillars
fungus Trichoderma
Baculoviruses (genus Nucleopolyhedrovirus)

55
Q

How does natural Bt work?

A

Sachets - dried spores - mixed with water and sprayed - eaten by caterpillar larvae - release toxin in gut of larvae - other insects unharmed

56
Q

How does genetically engineered Bt work?

A

toxin genes from Bt introduced in plants e.g. Bt cotton

57
Q

Organic farming uses __________ to enrich nutrient quality of the soil

A

Biofertilisers

58
Q

Main sources of biofertilisers

A

Bacteria, fungi, cyanobacteria

59
Q

Free-living Bacteria that can fix atmospheric nitrogen

A

Azospirillum (paddy fields) and Azotobacter

60
Q

________ forms symbiotic association with roots of leguminous plants (soyabean) and fixes atmospheric nitrogen

61
Q

What are mycorrhiza?

A

Fungi - plant symbiotic associations;
absorbs phosphorus from soil
passes to plant

e.g. genus Glomus

62
Q

What are the benefits of biofertiliser symbiotic associations to plants?

A

Resistance to root-borne pathogens
Tolerance to salinity
Tolerance to drought
Overall increase in plant growth

63
Q

In paddy fields ____________ is an important fertiliser

A

cyanobacteria

64
Q

Cyanobacteria are ________ microbes which can fix _________

A

autotrophic;

atmospheric Nitrogen

65
Q

Examples of cyanobacteria

A

Anabaena, Nostoc, Oscillatoria, Blue green algae

66
Q

What do blue green algae do as biofertilisers?

A

Add organic matter to the soil and increase its fertility

67
Q

Maximum concentration of alcohol in naturally fermented beverages is?

68
Q

Primary treatment of sewage involves removal of which of the following:

  1. dissolved substances
  2. stable substances
  3. toxic substances
  4. harmful bacteria
A

stable substances

69
Q

_________ bacterium is a clot bluster

A

Streptococcus pyogenes

70
Q

Baculoviruses are species ______ and _______ spectrum insecticides

A

species specific

narrow spectrum

71
Q

Modern detergents contain enzyme preparations of _______

A

alkaliphiles

72
Q

Which of the following helps in absorption of phosphorus from soil by plants?
rhizobium - anabaena - frankia - glomus

73
Q

Secondary sewage treatment is mainly a _______ process

mechanical - chemical - biological - physical?

A

biological

74
Q

_____________ is the most common substrate used in distilleries for the production of ethanol

75
Q

Which of the following is not used in organic farming?

Glomus - earthworm - oscillatoria - snail

76
Q

Which of the following plant species would you choose for the production of ethanol?
Brassica - Zea mays - Pongamia - Jatropha

77
Q

A compound which is produced by an organism that inhibits the growth of another organism is __________

A

antibiotic

78
Q

Antibiotics have no effect on viruses because _______

A

viruses show no metabolism of their own

79
Q

Single cell protein is rich in high quality protein but poor in fat. True or False?

80
Q

Trichoderma are free living fungi that are effective biocontrol agents of several pathogens. True or False?

81
Q

Baculoviruses are pathogens that attack insects and other anthropods. True or False?

82
Q

What is the first used biopesticide?

A

Baccilus thuringiensis

83
Q

Mycorrhiza is a symbiotic association between fungi e.g. Glomus and vascular plant. True or False?

84
Q

The varieties of cheese are known by their ________

A

characteristic taste, texture and flavor

specificity coming from microbes used

85
Q

Which of the following is NOT an example of industrial products fertilized by microbes?
beverages - antibiotics - curd - beer

86
Q

For fermentation of which of the following, are microbes not used?
fish - soyabean - bamboo leaves - cheese

A

bamboo leaves

87
Q

Major component of municipal waste is __________

A

human sewage

88
Q

The treatment of waste water is done by heterotrophic microbes (already present / adding during treatment / added after treatment) ?

A

Already present

89
Q

Ganga Action Plan and Yamuna action plan were initiated by ___________

A

Ministry of Environment and Forest

90
Q

IPM stands for

A

integrated pest management

91
Q

_________ is a nitrogen-fixing microbe associated with Azolla in rice fields

92
Q

A genetically engineered micro-organism used in bioremediation of oil spills is a species of:

A

Pseudomonas

93
Q 
Which of the following is wrongly matched?
Methanogens - gobar gas
Yeast - ethanol
Streptomycetes - antibiotic
Coliforms - vinegar
A

Coliforms - vinegar

94
Q

Curing of tea leaves is brought by activity of:

95
Q

Which of the following can be used in treatment of plant disease?
lactobacillus - trichoderma - chlorella - anabaena

A

trichoderma

Biology (NCERT) - Class XII (18 decks)

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