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Microbes in Human Welfare

Microbes in Human Welfare

Action PlanNotesQuestionsMock-Test
Study Action Plan (Sorted by Difficulty)
Bacillus thuringiensis and Bt Toxin
Accuracy: 50%
Total Attempted10
Total Correct5
Total Incorrect5
Difficulty Level:
Medium
Biochemical Oxygen Demand
Accuracy: 50%
Total Attempted4
Total Correct2
Total Incorrect2
Difficulty Level:
Medium
Biofertilisers and Organic Farming
Accuracy: 50%
Total Attempted10
Total Correct5
Total Incorrect5
Difficulty Level:
Medium
Methanogens in Rumen and Dung
Accuracy: 50%
Total Attempted2
Total Correct1
Total Incorrect1
Difficulty Level:
Medium
Diversity and Occurrence of Microbes
Accuracy: 60%
Total Attempted5
Total Correct3
Total Incorrect2
Difficulty Level:
Medium
Microbes in Sewage Treatment
Accuracy: 63%
Total Attempted19
Total Correct12
Total Incorrect7
Difficulty Level:
Medium
Bt Cotton
Accuracy: 67%
Total Attempted3
Total Correct2
Total Incorrect1
Difficulty Level:
Medium
Mycorrhiza and Glomus
Accuracy: 67%
Total Attempted9
Total Correct6
Total Incorrect3
Difficulty Level:
Medium
Secondary or Biological Treatment
Accuracy: 67%
Total Attempted9
Total Correct6
Total Incorrect3
Difficulty Level:
Medium
Baculoviruses and Nucleopolyhedrovirus
Accuracy: 73%
Total Attempted11
Total Correct8
Total Incorrect3
Difficulty Level:
Medium
Penicillin Discovery and Development
Accuracy: 75%
Total Attempted4
Total Correct3
Total Incorrect1
Difficulty Level:
Low
Fermented Dough: Idli, Dosa and Bread
Accuracy: 80%
Total Attempted5
Total Correct4
Total Incorrect1
Difficulty Level:
Low
Microbes in Production of Biogas
Accuracy: 80%
Total Attempted10
Total Correct8
Total Incorrect2
Difficulty Level:
Low
Organic Acids from Microbes
Accuracy: 80%
Total Attempted10
Total Correct8
Total Incorrect2
Difficulty Level:
Low
Sewage and Need for Treatment
Accuracy: 80%
Total Attempted5
Total Correct4
Total Incorrect1
Difficulty Level:
Low
Microbes in Industrial Products
Accuracy: 83%
Total Attempted29
Total Correct24
Total Incorrect5
Difficulty Level:
Low
Rhizobium in Legume Root Nodules
Accuracy: 83%
Total Attempted18
Total Correct15
Total Incorrect3
Difficulty Level:
Low
Microbes as Biofertilisers
Accuracy: 85%
Total Attempted20
Total Correct17
Total Incorrect3
Difficulty Level:
Low
Microbial Production of Chemicals and Enzymes
Accuracy: 88%
Total Attempted16
Total Correct14
Total Incorrect2
Difficulty Level:
Low
Cheese Production by Microbe
Accuracy: 91%
Total Attempted11
Total Correct10
Total Incorrect1
Difficulty Level:
Low
Antibiotics from Microbes
Accuracy: 93%
Total Attempted14
Total Correct13
Total Incorrect1
Difficulty Level:
Low
Microbes as Biocontrol Agents
Accuracy: 94%
Total Attempted32
Total Correct30
Total Incorrect2
Difficulty Level:
Low
Curd Formation by LAB
Accuracy: 100%
Total Attempted4
Total Correct4
Total Incorrect0
Difficulty Level:
Low
Cyanobacteria as Biofertilisers
Accuracy: 100%
Total Attempted1
Total Correct1
Total Incorrect0
Difficulty Level:
Low
Fermented Beverages
Accuracy: 100%
Total Attempted3
Total Correct3
Total Incorrect0
Difficulty Level:
Low
Free-Living Nitrogen Fixing Bacteria
Accuracy: 100%
Total Attempted3
Total Correct3
Total Incorrect0
Difficulty Level:
Low
Microbes in Household Products
Accuracy: 100%
Total Attempted11
Total Correct11
Total Incorrect0
Difficulty Level:
Low
Trichoderma as Biocontrol Fungus
Accuracy: 100%
Total Attempted6
Total Correct6
Total Incorrect0
Difficulty Level:
Low

Learning Objectives

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Learning Objectives

  • Identify the role of microbes in household products.
  • Discuss the importance of microbes in industrial products.
  • Explain the process of sewage treatment using microbes.
  • Describe the production of biogas and its significance.
  • Analyze the use of microbes as biocontrol agents in agriculture.
  • Evaluate the benefits of biofertilisers in soil fertility.

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Revision Notes & Summary

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Microbes in Human Welfare

8.1 Microbes in Household Products

  • Microbes are used in everyday products, such as curd from milk.
    • Lactic Acid Bacteria (LAB): Convert milk to curd, improving nutritional quality by increasing vitamin B12.
    • Fermentation: Used in making dough for foods like dosa and idli, producing CO₂ gas.

8.2 Microbes in Industrial Products

  • Microbes synthesize valuable products in industries, including beverages and antibiotics.
  • Industrial production requires large vessels called fermentors.

8.3 Microbes in Sewage Treatment

  • Microbes are used to treat sewage through activated sludge formation, recycling water in nature.

8.4 Microbes in Production of Biogas

  • Methanogens: Produce methane (biogas) while degrading plant waste, used as an energy source in rural areas.

8.5 Microbes as Biocontrol Agents

  • Biocontrol uses biological methods to manage pests and diseases, reducing reliance on harmful chemicals.

8.6 Microbes as Biofertilisers

  • Biofertilisers enrich soil nutrient quality, with sources including bacteria, fungi, and cyanobacteria.
    • Rhizobium: Fixes atmospheric nitrogen in leguminous plants.
    • Mycorrhiza: Fungi that enhance phosphorus absorption for plants.
    • Cyanobacteria: Fix nitrogen and add organic matter to soil.

Summary

  • Microbes play a crucial role in human welfare, with applications in food production, industrial processes, sewage treatment, energy production, pest control, and soil enrichment.
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Practice Test – MCQs, True/False

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Multiple Choice Questions

A.

Lactobacillus

B.

Saccharomyces cerevisiae

C.

Propionibacterium sharmanii

D.

Penicillium notatum
Correct Answer: C

Solution:

Propionibacterium sharmanii produces a large amount of CO2CO_2, which creates the characteristic holes in Swiss cheese.

Chapter Concept:

Cheese Production by Microbe

A.

A chemical substance produced by microbes that can kill or retard the growth of other microbes.

B.

A synthetic chemical used to enhance the growth of beneficial microbes.

C.

A naturally occurring compound that boosts the immune system of humans.

D.

A chemical agent used to sterilize surgical instruments.
Correct Answer: A

Solution:

Antibiotics are chemical substances produced by some microbes that can kill or retard the growth of other disease-causing microbes.

Chapter Concept:

Antibiotics from Microbes

A.

By fixing atmospheric nitrogen

B.

By absorbing phosphorus from the soil

C.

By producing antibiotics

D.

By increasing carbon dioxide levels
Correct Answer: B

Solution:

Mycorrhizal fungi, such as those from the genus Glomus, absorb phosphorus from the soil and pass it to the plant.

Chapter Concept:

Microbes as Biofertilisers

A.

They increase the soil's nitrogen content through symbiotic relationships.

B.

They directly kill harmful pests without affecting beneficial insects.

C.

They enhance the flavor and texture of agricultural produce.

D.

They reduce the need for irrigation by retaining soil moisture.
Correct Answer: A

Solution:

Biofertilisers, such as those involving Rhizobium, enrich the soil's nutrient quality by fixing atmospheric nitrogen into organic forms, which plants can use as nutrients.

Chapter Concept:

Biofertilisers and Organic Farming

A.

Biofertilisers are cheaper to produce

B.

Biofertilisers enrich soil nutrient quality without causing environmental pollution

C.

Biofertilisers increase the soil's pH

D.

Biofertilisers eliminate the need for pesticides
Correct Answer: B

Solution:

Biofertilisers enhance soil nutrient quality and are environmentally friendly, reducing the pollution associated with chemical fertilisers.

Chapter Concept:

Microbes as Biofertilisers

A.

They are broad-spectrum insecticides affecting all insects.

B.

They are used in biocontrol to specifically target certain insect species without harming non-target organisms.

C.

They are used to enhance plant growth directly.

D.

They are harmful to mammals and birds.
Correct Answer: B

Solution:

Baculoviruses are species-specific and used in biocontrol to target specific insect pests without affecting non-target organisms.

Chapter Concept:

Microbes as Biocontrol Agents

A.

Fix atmospheric nitrogen, enriching soil fertility.

B.

Produce antibiotics that protect plants from pathogens.

C.

Decompose organic matter to release carbon dioxide.

D.

Increase the water retention capacity of soil.
Correct Answer: A

Solution:

Cyanobacteria are known for their ability to fix atmospheric nitrogen, which is converted into organic forms usable by plants. This process enriches the soil with essential nutrients, making them effective biofertilisers, especially in paddy fields.

Chapter Concept:

Cyanobacteria as Biofertilisers

A.

Alexander Fleming, Louis Pasteur, and Robert Koch

B.

Alexander Fleming, Ernest Chain, and Howard Florey

C.

Ernest Chain, Robert Koch, and Howard Florey

D.

Louis Pasteur, Alexander Fleming, and Howard Florey
Correct Answer: B

Solution:

Alexander Fleming, Ernest Chain, and Howard Florey were awarded the Nobel Prize in 1945 for their work on Penicillin.

Chapter Concept:

Antibiotics from Microbes

A.

They fix atmospheric nitrogen while living freely in soil, enriching soil nitrogen content.

B.

They form symbiotic relationships with leguminous plants to fix nitrogen.

C.

They are involved in the decomposition of organic matter in soil.

D.

They are pathogens that cause diseases in plants.
Correct Answer: A

Solution:

Azospirillum and Azotobacter are free-living nitrogen-fixing bacteria that enrich the nitrogen content of the soil by fixing atmospheric nitrogen.

Chapter Concept:

Free-Living Nitrogen Fixing Bacteria

A.

Azospirillum

B.

Rhizobium

C.

Nostoc

D.

Saccharomyces cerevisiae
Correct Answer: B

Solution:

Rhizobium forms nodules on the roots of leguminous plants, where it fixes atmospheric nitrogen into compounds that the plant can use.

Chapter Concept:

Biofertilisers and Organic Farming

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Microbes in Human Welfare

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True or False

Correct Answer: True

Solution:

Penicillin, discovered by Alexander Fleming, was the first antibiotic. Its effectiveness was later demonstrated by Chain and Florey, who were awarded the Nobel Prize for their work.

Chapter Concept :

Antibiotics from Microbes

Correct Answer: False

Solution:

The primary treatment in sewage treatment involves the physical removal of particles through filtration and sedimentation, not biological degradation.

Chapter Concept :

Microbes in Sewage Treatment

Correct Answer: True

Solution:

Methanobacterium is a methanogen that plays a crucial role in the anaerobic digestion process, producing methane-rich biogas.

Chapter Concept :

Microbes in Production of Biogas

Correct Answer: True

Solution:

Microbes like Aspergillus niger and Acetobacter aceti are used for the production of citric acid and acetic acid, respectively, on an industrial scale.

Chapter Concept :

Microbes in Industrial Products

Correct Answer: True

Solution:

Methanobacterium is a methanogen that grows anaerobically on cellulosic material and produces methane, which is a major component of biogas.

Chapter Concept :

Microbes in Production of Biogas

Correct Answer: True

Solution:

Rhizobium forms symbiotic associations with leguminous plants to fix atmospheric nitrogen, while Azospirillum and Azotobacter can fix nitrogen while free-living in the soil, thus enriching the nitrogen content of the soil.

Chapter Concept :

Microbes as Biofertilisers

Correct Answer: True

Solution:

Bacillus thuringiensis (Bt) is a bacterium used as a microbial biocontrol agent. It produces a toxin that is effective against the larvae of certain insects, including butterfly caterpillars, without harming other insects.

Chapter Concept :

Microbes as Biocontrol Agents

Correct Answer: True

Solution:

Microbes are known to inhabit extreme environments, including thermal vents where temperatures can reach 100°C, as well as highly acidic environments.

Chapter Concept :

Diversity and Occurrence of Microbes

Correct Answer: True

Solution:

Lactic acid bacteria (LAB) such as Lactobacillus grow in milk and convert it into curd by producing acids that coagulate and partially digest milk proteins, thereby improving its nutritional quality.

Chapter Concept :

Microbes in Household Products

Correct Answer: True

Solution:

Alexander Fleming discovered Penicillin when he noticed that a mould, later identified as Penicillium notatum, inhibited the growth of Staphylococci bacteria on his culture plates.

Chapter Concept :

Antibiotics from Microbes

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