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Microbes in Human Welfare

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Microbes in Human Welfare

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Summary

Summary of Microbes in Human Welfare

  • Microbial Diversity: Microbes are present in various environments including soil, water, air, and within living organisms.
  • Microbes in Household Products:
    • Lactic acid bacteria (LAB) convert milk into curd, enhancing nutritional quality.
    • Yeast (Saccharomyces cerevisiae) is used in bread-making through fermentation.
    • Traditional foods like idli and dosa are made using fermented dough.
  • Microbes in Industrial Products:
    • Used to produce beverages and antibiotics on an industrial scale.
    • Fermentors are utilized for large-scale microbial growth.
  • Microbes in Sewage Treatment:
    • Microbes are employed in activated sludge processes to treat wastewater, aiding in water recycling.
  • Microbes in Biogas Production:
    • Methanogens produce biogas from plant waste, serving as an energy source in rural areas.
  • Microbes as Biocontrol Agents:
    • Biological methods are used to control pests and diseases, reducing reliance on harmful chemicals.
  • Microbes as Biofertilisers:
    • Organisms like Rhizobium fix atmospheric nitrogen, enriching soil fertility.
    • Fungi (mycorrhiza) enhance nutrient absorption for plants.
  • Importance of Microbes:
    • Essential for human welfare, contributing to food production, health, and environmental sustainability.

Learning Objectives

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.

Detailed Notes

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.

Exam Tips & Common Mistakes

Common Mistakes and Exam Tips

Common Pitfalls

  • Misunderstanding Microbial Roles: Students often confuse harmful microbes with beneficial ones. Remember that not all microbes are pathogenic; many play crucial roles in human welfare.
  • Neglecting the Importance of Biofertilisers: Many students overlook the significance of biofertilisers in agriculture, thinking only chemical fertilisers are effective. Understand the benefits of using organisms like Rhizobium and mycorrhizal fungi.
  • Confusing Sewage Treatment Processes: Be clear about the differences between primary and secondary sewage treatment. Mislabeling these processes can lead to incorrect answers.

Exam Tips

  • Focus on Applications: When studying microbes, emphasize their applications in daily life, such as in food production (e.g., curd, bread) and industrial processes (e.g., antibiotics, biogas).
  • Diagram Practice: Familiarize yourself with diagrams related to microbial processes, such as fermentation and sewage treatment plants, as they can be crucial for visual questions.
  • Understand Metabolic Processes: Be prepared to explain metabolic pathways, especially those leading to gas production in fermentation, as these are common exam questions.
  • Use Examples: When asked about the roles of microbes, use specific examples like Lactobacillus for curd or Saccharomyces cerevisiae for bread-making to illustrate your points.

Practice & Assessment

Multiple Choice Questions

A.

The pest population will increase due to resistance development.

B.

Non-target beneficial insects will also be affected.

C.

The pest population will decrease due to the toxin produced by Bt.

D.

The soil nutrient content will be significantly altered.
Correct Answer: C

Solution:

Bt produces a toxin that specifically targets certain pest larvae, reducing their population without affecting non-target insects.

A.

Rhizobium

B.

Aspergillus niger

C.

Penicillium notatum

D.

Saccharomyces cerevisiae
Correct Answer: A

Solution:

Rhizobium forms symbiotic associations with leguminous plants and fixes atmospheric nitrogen into organic forms, enriching the soil.

A.

Fixation of atmospheric nitrogen

B.

Increased phosphorus uptake

C.

Addition of organic matter to the soil

D.

Improvement of soil structure
Correct Answer: B

Solution:

Cyanobacteria primarily fix atmospheric nitrogen and add organic matter, but they do not directly increase phosphorus uptake.

A.

Saccharomyces cerevisiae

B.

Lactobacillus

C.

Acetobacter aceti

D.

Aspergillus niger
Correct Answer: A

Solution:

Saccharomyces cerevisiae, also known as brewer's yeast, is used for fermenting malted cereals and fruit juices to produce ethanol.

A.

Increased phosphorus uptake by plants

B.

Higher nitrogen content in the soil

C.

Improved resistance to fungal infections

D.

Enhanced drought resistance
Correct Answer: B

Solution:

Cyanobacteria are known for their ability to fix atmospheric nitrogen, thereby enriching the nitrogen content of the soil.

A.

Increased phosphorus availability in the soil

B.

Enhanced nitrogen fixation in the soil

C.

Improved resistance to fungal infections

D.

Higher potassium content in the soil
Correct Answer: B

Solution:

Cyanobacteria are known for their ability to fix atmospheric nitrogen, thereby enriching the nitrogen content of the soil, which is a primary benefit for the farmer.

A.

Penicillium notatum

B.

Aspergillus niger

C.

Streptococcus

D.

Monascus purpureus
Correct Answer: A

Solution:

Penicillium notatum is the mold from which the antibiotic Penicillin was first discovered.

A.

Producing antibiotics

B.

Creating synthetic plastics

C.

Manufacturing steel

D.

Producing fossil fuels
Correct Answer: A

Solution:

Microbes are used to produce antibiotics, which are significant for treating diseases.

A.

Rhizobium

B.

Saccharomyces cerevisiae

C.

Penicillium

D.

Propionibacterium
Correct Answer: A

Solution:

Rhizobium forms symbiotic associations with leguminous plants to fix atmospheric nitrogen into organic forms.

A.

Ethanol

B.

Lactic acid

C.

Acetic acid

D.

Butyric acid
Correct Answer: A

Solution:

During the fermentation process in brewing beer, yeast primarily converts sugars into ethanol and carbon dioxide. Ethanol is the main alcoholic component of beer.

A.

Rhizobium

B.

Azospirillum

C.

Nostoc

D.

Trichoderma
Correct Answer: B

Solution:

Azospirillum is known for forming symbiotic relationships with non-leguminous plants and fixing atmospheric nitrogen, enhancing soil fertility.

A.

Testing its spectrum of activity against various bacteria

B.

Increasing its concentration indefinitely

C.

Using it indiscriminately for all infections

D.

Combining it with any other antibiotic
Correct Answer: A

Solution:

Testing the antibiotic's spectrum of activity helps determine its effectiveness against specific bacterial strains.

A.

Increased resistance to root-borne pathogens

B.

Production of antibiotics

C.

Fermentation of dairy products

D.

Production of biogas
Correct Answer: A

Solution:

Mycorrhizal associations in plants, particularly with fungi like Glomus, increase resistance to root-borne pathogens, enhance tolerance to salinity and drought, and improve plant growth.

A.

To convert milk into cheese

B.

To convert milk into curd

C.

To produce ethanol

D.

To produce acetic acid
Correct Answer: B

Solution:

Lactic acid bacteria (LAB) convert milk into curd by producing acids that coagulate and partially digest milk proteins.

A.

They increase the use of chemical pesticides.

B.

They help in eradicating all insects.

C.

They reduce the need for toxic chemicals.

D.

They promote the growth of weeds.
Correct Answer: C

Solution:

Biocontrol agents help reduce the dependence on toxic chemicals and pesticides in agriculture.

A.

Increased use of chemical fertilizers

B.

Reduction in greenhouse gas emissions

C.

Higher water consumption in agriculture

D.

Decreased soil fertility
Correct Answer: B

Solution:

Biogas production from microbial activity helps in reducing greenhouse gas emissions by providing a renewable energy source.

A.

They produce antibiotics.

B.

They fix atmospheric nitrogen into organic forms.

C.

They decompose organic matter.

D.

They produce ethanol.
Correct Answer: B

Solution:

Rhizobium bacteria form symbiotic associations with leguminous plants and fix atmospheric nitrogen into forms that plants can use as nutrients.

A.

Production of antibiotics

B.

Biocontrol agent against plant pathogens

C.

Fermentation of dairy products

D.

Biofertiliser for nitrogen fixation
Correct Answer: B

Solution:

Trichoderma species are effective biocontrol agents of several plant pathogens.

A.

Production of lactic acid

B.

Increase in pH level

C.

Production of ethanol

D.

Formation of curd
Correct Answer: C

Solution:

Saccharomyces cerevisiae, commonly known as brewer's yeast, ferments sugars to produce ethanol, which would indicate successful fermentation.

A.

Increased atmospheric nitrogen fixation

B.

Enhanced photosynthetic rate of plants

C.

Improved drought resistance in plants

D.

Increased resistance to insect pests
Correct Answer: A

Solution:

Cyanobacteria are known for their ability to fix atmospheric nitrogen, which can enrich the soil with nitrogen and improve plant growth, making them beneficial as biofertilizers.

A.

Producing alcoholic beverages with extended shelf life

B.

Enhancing the flavor of dairy products

C.

Increasing the nutritional content of bread

D.

Improving the texture of fermented vegetables
Correct Answer: A

Solution:

The yeast produces ethanol, which is typical for alcoholic beverages, and the byproduct inhibits bacterial growth, potentially extending the shelf life of these beverages.

A.

Inadequate supply of cattle dung

B.

Excessive use of chemical fertilizers in nearby fields

C.

High ambient temperature

D.

Presence of methanogenic bacteria
Correct Answer: A

Solution:

Cattle dung is a primary substrate for biogas production. Inadequate supply can lead to reduced methane production.

A.

Trichoderma polysporum

B.

Monascus purpureus

C.

Streptococcus

D.

Penicillium notatum
Correct Answer: A

Solution:

Trichoderma polysporum produces Cyclosporin A, a bioactive molecule used as an immunosuppressive agent in organ-transplant patients.

A.

Producing antibiotics

B.

Fixing atmospheric nitrogen

C.

Producing ethanol

D.

Decomposing organic matter
Correct Answer: B

Solution:

Cyanobacteria, such as Anabaena and Nostoc, fix atmospheric nitrogen, enriching the soil in paddy fields.

A.

Lactobacillus

B.

Saccharomyces cerevisiae

C.

Propionibacterium sharmanii

D.

Aspergillus niger
Correct Answer: B

Solution:

Saccharomyces cerevisiae, also known as baker's yeast, is used in the fermentation of bread.

A.

Acetobacter aceti

B.

Clostridium butylicum

C.

Aspergillus niger

D.

Lactobacillus
Correct Answer: C

Solution:

Aspergillus niger, a fungus, is used for the industrial production of citric acid.

A.

Propionibacterium sharmanii

B.

Lactobacillus

C.

Streptococcus

D.

Bacillus thuringiensis
Correct Answer: A

Solution:

Propionibacterium sharmanii is known for producing large amounts of CO₂, which creates the characteristic holes in Swiss cheese.

A.

Lactic acid fermentation

B.

Alcoholic fermentation

C.

Acetic acid fermentation

D.

Butyric acid fermentation
Correct Answer: B

Solution:

The puffed-up appearance of dough used in making foods like dosa and idli is due to the production of CO₂ gas during alcoholic fermentation by bacteria.

A.

Clostridium butylicum

B.

Aspergillus niger

C.

Acetobacter aceti

D.

Lactobacillus
Correct Answer: C

Solution:

Acetobacter aceti is a bacterium used for the production of acetic acid.

A.

Absorbing phosphorus from soil

B.

Fixing nitrogen

C.

Producing ethanol

D.

Generating biogas
Correct Answer: A

Solution:

Mycorrhiza, formed by fungi like Glomus, helps plants by absorbing phosphorus from the soil and passing it to the plant.

A.

Saccharomyces cerevisiae

B.

Lactobacillus

C.

Clostridium butylicum

D.

Aspergillus niger
Correct Answer: A

Solution:

Saccharomyces cerevisiae, commonly known as brewer's yeast, is used for fermenting malted cereals and fruit juices to produce ethanol.

A.

Rhizobium

B.

Azospirillum

C.

Glomus

D.

Saccharomyces cerevisiae
Correct Answer: C

Solution:

Glomus is a genus of fungi that forms mycorrhizal associations with plant roots, helping plants absorb phosphorus and providing resistance to salinity and drought, thus enhancing plant growth in saline soils.

A.

Lactobacillus

B.

Saccharomyces cerevisiae

C.

Propionibacterium sharmanii

D.

Penicillium notatum
Correct Answer: C

Solution:

The large holes in Swiss cheese are due to the production of a large amount of CO₂ by Propionibacterium sharmanii.

A.

Methane (CH₄)

B.

Carbon dioxide (CO₂)

C.

Hydrogen sulfide (H₂S)

D.

Nitrogen (N₂)
Correct Answer: A

Solution:

Biogas primarily consists of methane (CH₄) and carbon dioxide (CO₂), with methane being the major component produced by methanogens during the anaerobic digestion of organic matter such as cattle dung.

A.

Testing its ability to inhibit bacterial growth in vitro

B.

Determining its effect on viral replication

C.

Assessing its impact on plant growth

D.

Evaluating its ability to ferment sugars
Correct Answer: A

Solution:

To ensure the effectiveness of a new antibiotic in treating bacterial infections, it is crucial to test its ability to inhibit bacterial growth in vitro. This step helps determine its potential as an antibacterial agent.

A.

Rhizobium with legumes

B.

Azospirillum with cereals

C.

Glomus forming mycorrhiza with the crops

D.

Lactobacillus in the soil
Correct Answer: C

Solution:

Glomus forms mycorrhizal associations with plant roots, enhancing phosphorus uptake and providing other growth benefits.

A.

Fermentation of malted cereals

B.

Distillation of fermented broth

C.

Use of Saccharomyces cerevisiae

D.

Fermentation of fruit juices
Correct Answer: B

Solution:

Non-distilled alcoholic drinks like wine and beer are produced without distillation, unlike whisky or rum.

A.

Trichoderma polysporum

B.

Monascus purpureus

C.

Aspergillus niger

D.

Clostridium butylicum
Correct Answer: A

Solution:

Cyclosporin A is produced by the fungus Trichoderma polysporum.

A.

Increases resistance to root-borne pathogens

B.

Produces ethanol

C.

Fixes atmospheric nitrogen

D.

Produces antibiotics
Correct Answer: A

Solution:

Mycorrhiza, formed by fungi like Glomus, helps plants by increasing resistance to root-borne pathogens and improving nutrient uptake.

A.

Lactobacillus

B.

Saccharomyces cerevisiae

C.

Acetobacter aceti

D.

Aspergillus niger
Correct Answer: B

Solution:

Saccharomyces cerevisiae, commonly called brewer's yeast, is used for fermenting malted cereals and fruit juices to produce ethanol.

A.

Curd

B.

Raw meat

C.

Fresh fruit juice

D.

Cooked rice
Correct Answer: A

Solution:

Curd is produced by the fermentation of milk by lactic acid bacteria (LAB), making it the most appropriate food sample for demonstrating the presence of LAB.

A.

Increased nitrogen fixation

B.

Enhanced phosphorus uptake

C.

Improved photosynthesis efficiency

D.

Greater resistance to bacterial infections
Correct Answer: B

Solution:

Mycorrhizal fungi are known to enhance phosphorus uptake from the soil, which is a direct benefit for plant growth.

A.

Reduction in methane emissions

B.

Decrease in water pollution

C.

Production of renewable energy

D.

Increase in agricultural yield
Correct Answer: C

Solution:

Biogas plants produce renewable energy by converting organic waste into methane, which can be used as a source of energy.

A.

Ladybird beetles

B.

Bacillus thuringiensis

C.

Trichoderma species

D.

Nucleopolyhedrovirus
Correct Answer: A

Solution:

Ladybird beetles are natural predators of aphids and are effective in controlling their populations in an organic farming system.

A.

Testing the antibiotic on viral infections

B.

Determining the antibiotic's spectrum of activity

C.

Increasing the antibiotic's production yield

D.

Enhancing the antibiotic's flavor for oral consumption
Correct Answer: B

Solution:

Determining the spectrum of activity is crucial to understand which bacterial infections the antibiotic can effectively treat.

A.

To produce ethanol

B.

To coagulate and partially digest milk proteins

C.

To produce antibiotics

D.

To ferment malted cereals
Correct Answer: B

Solution:

Lactic acid bacteria (LAB) grow in milk and produce acids that coagulate and partially digest the milk proteins, converting milk into curd.

A.

Trichoderma

B.

Bacillus thuringiensis

C.

Azotobacter

D.

Penicillium
Correct Answer: B

Solution:

Bacillus thuringiensis is a microbial biocontrol agent that produces toxins lethal to caterpillars, making it suitable for controlling caterpillar infestations.

A.

It is ripened by a specific fungus

B.

It has large holes due to CO₂ production

C.

It is made using brewer's yeast

D.

It is fermented by Bacillus thuringiensis
Correct Answer: B

Solution:

The large holes in Swiss cheese are due to the production of a large amount of CO₂ by the bacterium Propionibacterium sharmanii.

A.

Distillation

B.

Fermentation

C.

Filtration

D.

Pasteurization
Correct Answer: B

Solution:

Fermentation is the process where yeast converts sugars into ethanol and carbon dioxide. Optimizing fermentation conditions will maximize ethanol production.

A.

Saccharomyces cerevisiae

B.

Lactobacillus

C.

Rhizobium

D.

Penicillium notatum
Correct Answer: A

Solution:

Saccharomyces cerevisiae, also known as brewer's yeast, is used for fermenting malted cereals and fruit juices to produce ethanol.

A.

Bacillus thuringiensis

B.

Trichoderma species

C.

Penicillium notatum

D.

Streptococcus species
Correct Answer: A

Solution:

Bacillus thuringiensis is used as a microbial biocontrol agent to control butterfly caterpillars. It releases toxins that kill the caterpillar larvae.

True or False

Correct Answer: False

Solution:

Microbes are present even in extreme environments where no other life form could exist, such as deep inside geysers and highly acidic environments.

Correct Answer: False

Solution:

Several microbes are useful to humans, such as those used in the production of curd, bread, and antibiotics.

Correct Answer: True

Solution:

Biofertilisers consist of organisms like bacteria, fungi, and cyanobacteria that enrich the soil's nutrient quality, reducing the need for chemical fertilisers.

Correct Answer: True

Solution:

The excerpt explains that biofertilisers, such as bacteria, fungi, and cyanobacteria, enrich the nutrient quality of the soil by fixing atmospheric nitrogen and other processes.

Correct Answer: False

Solution:

Microbes are present even in extreme environments such as deep inside geysers, under snow, and in highly acidic environments.

Correct Answer: False

Solution:

Microbes are present everywhere, including in air, inside bodies, and in extreme environments.

Correct Answer: True

Solution:

Bacteria and fungi are indeed used to impart specific characteristics to cheese.

Correct Answer: True

Solution:

Microbes are used to produce industrial products such as lactic acid, acetic acid, and alcohol.

Correct Answer: True

Solution:

Bacillus thuringiensis produces toxins that specifically target and kill insect larvae, such as butterfly caterpillars, without affecting other insects.

Correct Answer: True

Solution:

Biogas plants are often built in rural areas where cattle dung is readily available, making it a viable source of energy.

Correct Answer: True

Solution:

Rhizobium bacteria form symbiotic relationships with leguminous plants, fixing atmospheric nitrogen into forms that the plant can use.

Correct Answer: False

Solution:

Biocontrol measures help reduce the dependence on chemical pesticides but do not completely eliminate their need.

Correct Answer: False

Solution:

Cyanobacteria are autotrophic microbes that can fix atmospheric nitrogen in both aquatic and terrestrial environments.

Correct Answer: True

Solution:

Biogas plants are more often built in rural areas where cattle dung is available in large quantities.

Correct Answer: True

Solution:

Biocontrol agents, such as certain bacteria and fungi, are used to control pests and diseases, reducing the need for chemical pesticides.

Correct Answer: True

Solution:

Microbes are known to exist in extreme environments like thermal vents and under thick layers of snow, showcasing their adaptability.

Correct Answer: False

Solution:

Antibiotics are chemical substances produced by microbes that kill or retard the growth of disease-causing microbes, thus benefiting human life.

Correct Answer: True

Solution:

Microbes like bacteria and many fungi can be grown on nutritive media to form colonies that can be seen with the naked eyes.

Correct Answer: False

Solution:

Microbes are present in extreme environments such as deep inside geysers at temperatures as high as 100°C, under thick snow layers, and in highly acidic environments.

Correct Answer: False

Solution:

The production of curd from milk involves micro-organisms such as Lactobacillus and other lactic acid bacteria (LAB), not yeast.

Correct Answer: False

Solution:

Biocontrol measures help reduce our dependence on toxic chemicals and pesticides.

Correct Answer: True

Solution:

Cyanobacteria, such as Anabaena and Nostoc, are used as biofertilisers due to their ability to fix atmospheric nitrogen.

Correct Answer: False

Solution:

Microbes are present even at extreme sites such as deep inside geysers where the temperature may be as high as 100°C.

Correct Answer: True

Solution:

Biofertilisers, which include bacteria, fungi, and cyanobacteria, enhance soil fertility by fixing atmospheric nitrogen and improving nutrient content.

Correct Answer: False

Solution:

The primary role of microbes like Lactobacillus in the production of curd is to convert milk into curd by producing acids that coagulate and partially digest milk proteins. Increasing vitamin B12 is an additional benefit.

Correct Answer: True

Solution:

Biofertilisers enrich the nutrient quality of the soil and can reduce dependence on chemical fertilisers.

Correct Answer: True

Solution:

Antibiotics are indeed chemical substances produced by some microbes to kill or retard the growth of other microbes.

Correct Answer: False

Solution:

Not all microbes are pathogenic; many are useful to humans in diverse ways, such as in food production and biocontrol.

Correct Answer: True

Solution:

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

Correct Answer: True

Solution:

Methanogens are microbes that produce methane (biogas) while degrading plant waste, which is used as an energy source.

Correct Answer: False

Solution:

Biocontrol methods use biological means, such as natural predation, to control pests, reducing the need for toxic chemicals.

Correct Answer: False

Solution:

Antibiotics are chemical substances produced by some microbes that can kill or retard the growth of other disease-causing microbes, not just bacteria, and are used to treat various infections.

Correct Answer: True

Solution:

The excerpt mentions that microbes are present in extreme conditions such as deep inside geysers where temperatures may be as high as 100°C and in highly acidic environments.

Correct Answer: False

Solution:

Biogas plants are often built in rural areas where cattle dung is available in large quantities.

Correct Answer: False

Solution:

Biogas plants are more often built in rural areas where cattle dung is available in large quantities.

Correct Answer: True

Solution:

The text mentions that wine and beer are produced by fermenting malted cereals and fruit juices with yeast, without distillation.

Correct Answer: True

Solution:

Bacillus thuringiensis is used as a microbial biocontrol agent to control butterfly caterpillars by releasing toxins in the larvae's gut.

Correct Answer: False

Solution:

Biogas plants are more often built in rural areas where cattle dung is available in large quantities.

Correct Answer: False

Solution:

Not all microbes are harmful; many are beneficial and are used in various applications such as food production, medicine, and agriculture.

Correct Answer: True

Solution:

Biofertilisers like Rhizobium and cyanobacteria fix atmospheric nitrogen into forms usable by plants.

Correct Answer: True

Solution:

Trichoderma species are free-living fungi that are effective biocontrol agents of several plant pathogens.

Correct Answer: False

Solution:

Penicillin was the first antibiotic discovered, but it was a chance discovery by Alexander Fleming.

Correct Answer: True

Solution:

Bread dough is fermented using baker's yeast, Saccharomyces cerevisiae.

Correct Answer: True

Solution:

Biofertilisers are organisms that enrich the nutrient quality of the soil, and the main sources include bacteria, fungi, and cyanobacteria.

Correct Answer: True

Solution:

Microbes, especially yeasts, are used for fermenting malted cereals and fruit juices to produce beverages like wine and beer.

Correct Answer: False

Solution:

Not all microbes are pathogenic; many are beneficial to humans, such as those used in the production of antibiotics, fermented foods, and biofertilisers.

Correct Answer: False

Solution:

While some antibiotics, like Penicillin, are derived from fungi, others are derived from bacteria.