Microbes In Human Welfare
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Select the correct species which does not have the ability to fix atmospheric nitrogen?
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Nostoc
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Spirogyra
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Azotobacter
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Anabaena
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This online test titled 'Microbes in Human Welfare' assesses understanding of microbial applications in agriculture and food. It covers topics like nitrogen fixation, biological pest control, and microbial fermentation, relevant for students and professionals in biology and biotechnology.
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- 2.
The aquatic fern essential for paddy fields is
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Marsilea
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Azolla
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Ophioglossum
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Adiantum
Correct Answer
A. AzollaExplanation
Azolla is the correct answer because it is an aquatic fern that is essential for paddy fields. Azolla is commonly used in rice cultivation as a biofertilizer and a natural weed suppressant. It forms a symbiotic relationship with a nitrogen-fixing cyanobacterium, which helps in enriching the soil with nitrogen. Azolla also provides shade to the paddy fields, reducing water evaporation and preventing the growth of unwanted weeds. Therefore, Azolla plays a vital role in maintaining the health and productivity of paddy fields.Rate this question:
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- 3.
Azotobacter and Bacillus polymyxa are the examples of
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Symbiotic N2 fixers
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Non-symbiotic N2 fixer
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Pathogenic bacteria
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Decomposers
Correct Answer
A. Non-symbiotic N2 fixerExplanation
Azotobacter and Bacillus polymyxa are examples of non-symbiotic N2 fixers because they are able to fix atmospheric nitrogen into a usable form without forming a symbiotic relationship with other organisms. These bacteria have the ability to convert nitrogen gas into ammonia, which can then be used by plants for growth and development. Unlike symbiotic N2 fixers, such as Rhizobium bacteria that form nodules on legume roots, Azotobacter and Bacillus polymyxa are free-living bacteria that can fix nitrogen in the soil independently.Rate this question:
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- 4.
Biological control of agricultural pests unlike chemical control is
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Very expensive
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Toxic
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Self perpetuating
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Polluting
Correct Answer
A. Self perpetuatingExplanation
Biological control of agricultural pests is self-perpetuating, meaning that once the natural predators or parasites are introduced, they can reproduce and continue to control the pest population without the need for additional intervention. This is in contrast to chemical control, which requires repeated applications of pesticides that can be expensive, toxic, and polluting. Biological control offers a more sustainable and environmentally friendly approach to pest management in agriculture.Rate this question:
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- 5.
Integrated pest management programme (IPM) emphasizes on
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Biological control
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Confusion technique
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Pesticides
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None of these
Correct Answer
A. Biological controlExplanation
The correct answer is Biological control. Integrated pest management (IPM) is an approach that focuses on using natural methods to control pests, rather than relying solely on pesticides. Biological control involves the use of natural enemies, such as predators, parasites, and pathogens, to regulate pest populations. This method is considered more sustainable and environmentally friendly compared to the use of pesticides, as it reduces the reliance on chemical interventions and promotes the natural balance of ecosystems.Rate this question:
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- 6.
Idly batter is fermented by
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Lactic acid fungi
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Lactic
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Acetic acid fungi
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Acetic acid Bacteria
Correct Answer
A. LacticExplanation
Idly batter is fermented by lactic acid bacteria. These bacteria convert the carbohydrates present in the batter into lactic acid through the process of fermentation. This fermentation process gives idly its characteristic fluffy and soft texture. Lactic acid bacteria are commonly found in the environment and are also used in the fermentation of other food products such as yogurt and sauerkraut.Rate this question:
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- 7.
Fungal pectinase is produced by
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Aspergillus niger
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Aspergillus wentii
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Aspergillus megaterium
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Both a and b
Correct Answer
A. Both a and bExplanation
Fungal pectinase is produced by both Aspergillus niger and Aspergillus wentii. Pectinase is an enzyme that breaks down pectin, a complex carbohydrate found in the cell walls of plants. Aspergillus niger and Aspergillus wentii are both types of fungi known for their ability to produce pectinase. Therefore, the correct answer is "both a and b".Rate this question:
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- 8.
The inexpensive and less complicated step of sewage water treatment is
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Primary treatment
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Secondary treatment
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Tertiary treatment
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None of these
Correct Answer
A. Primary treatmentExplanation
Primary treatment is the initial step in sewage water treatment. It involves the physical removal of large solids and floating materials through processes such as screening and sedimentation. This step helps to reduce the amount of organic matter and suspended solids in the wastewater. Primary treatment is considered less expensive and less complicated compared to secondary and tertiary treatment processes, which involve more advanced and specialized methods for further purification of the wastewater. Therefore, primary treatment is the correct answer in this case.Rate this question:
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- 9.
Bt stands for
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Bacterum thuringiensis
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Bacterium thuringensis
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Bacillus turingenses
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Bacillus thuringiensis
Correct Answer
A. Bacillus turingenses -
- 10.
Salts of nitrogen and phosphorous must be removed from treated sewage water as they cause
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harm
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Spoilage
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Eutrophication
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Eutrophism
Correct Answer
A. EutrophismExplanation
Eutrophism is the correct answer because salts of nitrogen and phosphorus in treated sewage water can contribute to eutrophication. Eutrophication is the process where excessive nutrients, such as nitrogen and phosphorus, enter a body of water and promote the growth of algae and other aquatic plants. This excessive growth can deplete oxygen levels in the water, leading to harm and spoilage of aquatic ecosystems. Therefore, removing salts of nitrogen and phosphorus is necessary to prevent eutrophism and its negative impacts on water bodies.Rate this question:
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- 11.
Symbiotic association between a fungus and roots of higher plants is called
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Mycelium
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Mycorrhiza
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Helotism
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None of these
Correct Answer
A. MycorrhizaExplanation
Mycorrhiza is the correct answer because it refers to the symbiotic association between a fungus and the roots of higher plants. This association is beneficial for both the fungus and the plant, as the fungus helps in nutrient absorption for the plant while receiving carbohydrates from the plant in return. Mycelium is a term used to describe the vegetative part of a fungus, and helotism is not related to the association between fungi and plant roots.Rate this question:
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- 12.
BOD stands for
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Biochemical oxygen demand
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Biophysical oxygen demand
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Biological oxygen demand
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All of these
Correct Answer
A. Biological oxygen demandExplanation
BOD stands for Biological Oxygen Demand. It is a measure of the amount of dissolved oxygen needed by aerobic biological organisms in a body of water to break down organic material present in a given time period. This term is commonly used in environmental science and wastewater treatment to assess water quality and the level of organic pollution in water bodies.Rate this question:
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- 13.
Acetobacter aceti is involved in production of
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Lactic acid
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Acetic acid
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Citric acid
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Butyric acid
Correct Answer
A. Acetic acidExplanation
Acetobacter aceti is involved in the production of acetic acid. Acetic acid is a weak acid that is commonly found in vinegar and is used in various industries such as food, pharmaceutical, and chemical. Acetobacter aceti is a type of bacteria that can oxidize ethanol to produce acetic acid through a process called acetification. This bacterium is commonly used in the production of vinegar and plays a crucial role in converting ethanol into acetic acid, giving vinegar its characteristic sour taste and aroma.Rate this question:
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- 14.
Microbes are used to kill harmful pests. This process is called
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Bio microbial action
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Bio contro
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Bio care
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None of these
Correct Answer
A. Bio controExplanation
Microbes are used to kill harmful pests, which is known as bio control. Bio control involves the use of living organisms, such as bacteria, fungi, or viruses, to control pests and diseases in agriculture or other settings. These beneficial microbes can target and eliminate specific pests, reducing the need for chemical pesticides and promoting a more sustainable and environmentally friendly approach to pest management.Rate this question:
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- 15.
Now the day came when we need to use
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Chemical fertilizers
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N-P-K fertilizers
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Bio fertilizers
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All of these
Correct Answer
A. Bio fertilizersExplanation
The correct answer is "Bio fertilizers" because they are natural fertilizers that contain beneficial microorganisms, such as bacteria, fungi, and algae, which help improve soil fertility and plant growth. Unlike chemical fertilizers, bio fertilizers do not contain harmful chemicals that can harm the environment or human health. Additionally, bio fertilizers can enhance nutrient uptake, increase soil fertility, and promote plant growth in a sustainable and eco-friendly manner. Therefore, in the given scenario, when there is a need to use fertilizers, using bio fertilizers would be the most suitable option.Rate this question:
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Current Version
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Mar 20, 2023Quiz Edited by
ProProfs Editorial Team -
Jan 16, 2014Quiz Created by
Tanmay Shankar
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