Microbes in Human Welfare
CBSE Class 12 Biology · 89 board questions from this chapter; 87 listed below, 2022–2026
- Microbes commonly used in kitchen are2026
- Some cyanobacteria in aquatic and terrestrial environment that enrich the soil by fixing nitrogen are:2026
- Monascus purpureus is a yeast used commercially in the production of which one of the following?2026
- Microbes used for biocontrol of pest butterfly caterpillars is:2026
- Bacillus thuringiensis is used to control which one of the following pathogens/pests?2026
- Assertion: Activated sludge contains large population of bacteria. Reason (R): These bacteria help in anaerobic digestion of…2026
- Assertion: Genetically modified microbes help in crop protection. Reason (R): Bacillus thuringiensis (Bt) bacteria control…2026
- Assertion: Nucleopolyhedrovirus are useful, as they are good biological control agents. Reason (R): They are species-specific…2026
- Assertion: Microbes are used for commercial production of alcohol and beverages. Reason (R): Yeast converts glucose into ethanol…2026
- Assertion: Flocs are masses of bacteria associated with fungal filaments in secondary treatment of sewage. Reason (R): Flocs help…2026
- Assertion: Nucleopolyhedrovirus are useful as they are good biocontrol agents. Reason (R): They are species-specific, narrow…2026
- Assertion: Trichoderma species are free living fungi that are very common in the root ecosystems. Reason (R): They are effective…2026
- Assertion: Besides curdling of milk, LAB also improves its nutritional quality by increasing Vitamin B12. Reason (R): LAB, when…2026
- What is the role of LAB (Lactic Acid Bacteria) in preparation of curd? Mention two health benefits of consuming curd.2026
- A laboratory assistant collected three water samples, namely river water, untreated sewage water and secondary effluent…2026
- After significant reduction of BOD during secondary treatment of sewage, what further processes are carried out? Mention any one…2026
- Study the flow chart and answer the following questions: Identify A, B and C in the flow chart. Give one another example of…2026
- Explain how the following microbes act as biocontrol agents: Bacillus thuringiensis Nucleopolyhedrovirus2026
- Mention a product of human welfare obtained with the help of each one of the following: Saccharomyces cerevisiae…2026
- Cow dung and water are mixed and fed into a biogas plant to allow digestion of biowastes. The person performing this process says…2026
- Who discovered Penicillin and how? Explain. Why is this discovery considered accidental? In what way did it prove to be a…2026
- (i) Name the protozoan species that is responsible for causing the most serious and even fatal malarial disease. (ii) Name the…2026
- Match the items in Column-A with that of Column-B: Choose the option that matches the items of Column A with that of B correctly:2025
- The process of mineralization by microorganisms help in the release of:2025
- For commercial and industrial production of citric acid, which one of the following microbes is used?2025
- Name the microbe that is used as biocontrol agent for controlling pest butterfly caterpillars:2025
- Large scale industrial production of streptokinase for human welfare is done using the microbe:2025
- Large holes in 'Swiss cheese' are formed by the activity of microbes:2025
- Bioactive molecule Cyclosporin A used for human welfare is derived from:2025
- Bottled fruit juices are clearer as compared to those made at home, as they are clarified by the use of:2025
- Large scale industrial production of citric acid for human welfare is done using the microbe:2025
- Certain viruses used as biological control agents belong to the genus:2025
- Bioactive molecule statins used for human welfare are derived from:2025
- Large scale industrial production of Butyric acid for human welfare is done using the microbe:2025
- Identify the organism whose product has been commercialised as blood cholesterol lowering agent.2025
- Assertion: Swiss cheese is characterized by large holes due to CO_2 production. Reason (R): It is ripened by growing a specific…2025
- Assertion: While working on Staphylococci, Alexander Fleming observed that Penicillium notatum inhibits the growth of bacteria.…2025
- Assertion: Biogas plants are more often built in rural areas. Reason (R): The excreta or gobar of cattle is rich in…2025
- Student to attempt either option- or: How are morphine and heroin related? Mention their effect on the human body. OR (i) Name an…2025
- Ravi lives in a village where he suggested to the local farmers to introduce a fungus as biofertilizer into their crop fields.…2025
- Write the full form of BOD. Define BOD. Explain how it is a measure of the organic matter present in the water body.2025
- Explain the biological treatment of primary effluent when passed into the large aeration tanks in a sewage treatment plant (STP).2025
- What do you mean by activated sludge in an STP? Explain the biological treatment of the major part of the sludge transferred from…2025
- Study the figure given below and answer the questions that follow. Identify the figure and state its importance. Why is air…2025
- During biological treatment of sewage, the masses of bacteria held together by fungal filaments to form mesh like structures are…2024
- A list of organisms is given in column 'R', whereas in column 'S' a list of products produced by them: Select the option where…2024
- The first antibiotic was discovered accidentally by A while working on B. 'A' and 'B' are 12024
- Given below is a list of some commercially important products in column A, whereas in column B are names of source organisms:…2024
- Answer the questions based on the typical biogas plant diagram given below: Identify 'X', 'Y' and 'Z'. Why is dung preferred for…2024
- List the events that reduce the Biochemical Oxygen Demand (BOD) of a primary effluent during sewage treatment.2024
- Explain how are plants benefitted by their association with “Glomus species”.2024
- Different varieties of cheese are known by their characteristic texture, flavour and taste, the specificity coming from the…2024
- Identify a, b, c, d, e and f in the table given below: 3 Sl. No. Organism Bioactive Molecule Use 1. Monascus purpureus a b 2. c d…2024
- Explain the role of the following during the sewage treatment: flocs anaerobic sludge digester2024
- (i) List two major reasons for using cow-dung in a biogas plant instead of using domestic sewage. (ii) Mention one use of the…2024
- How do the following organisms act as bio-fertilisers? Explain. Mycorrhiza Anabaena Rhizobium2024
- Identify a, b, c, d, e and f in the table given below: 3 Sl. No. Organism Bioactive Molecule Use 1. Monascus purpureus a b 2. c d…2024
- (i) Name and explain the property present in normal cells but is lost in cancer cells. (ii) All normal human cells have genes…2024
- The graph plotted below is based on the data collected by biology students with respect to the levels of oxygen at the specific…2023
- Which one of the following fixes the atmospheric nitrogen but is not an autotroph?2023
- Given below are the list of the commercially important products and their source organisms. Select the option that gives the…2023
- Which one among the following biofertilizers does not fix atmospheric nitrogen?2023
- Assertion: Biologists are sure about how many prokaryotic species are living now. Reason (R): The conventional taxonomic methods…2023
- Write the first step the primary effluent undergoes when it enters the secondary treatment plant and state the purpose. What is…2023
- (i) Give an example of a genus of fungi that forms mycorrhizial association with plants. (ii) How does the plant derive benefits…2023
- Name the two institutes which developed the technology of biogas production in India. Explain the main principle used in this…2023
- Certain specific bacterial spores are mixed in water and sprayed over Brassica crop to control butterfly catterpillars. Name this…2023
- (i) Give an example of a genus of virus used as narrow spectrum insecticidal biocontrol agent. (ii) How does its use serve as an…2023
- Explain the role of microorganisms in the following: Reducing the sugar content in grape juice Production of a fuel2023
- Treatment of wastewater is done in a sewage treatment plant to make it less polluting. Explain the following with reference to…2023
- Many members of genus Glomus form a mycorrhizial association with plants. Elaborate how is this association beneficial to the…2022
- State the most important contribution of the following microbes for human welfare: Monascus purpureus Trichoderma Polysporum2022
- Lactic Acid Bacteria (LAB) sets milk into curd and also plays a very beneficial role for human health. Give any two suitable…2022
- Mention the common bacterium found in the anaerobic sludge during sewage treatment and also in the rumen of cattle. How is this…2022
- "Curd is easier to digest by humans than milk." Justify, giving two suitable reasons.2022
- Can we use slurry of human excreta instead of cowdung slurry to produce biogas in a typical biogas plant? Support your answer…2022
- State the impact of constant mechanical agitation and pumping of air in the aeration tank on the sewage during the biological…2022
- Some of the microbes used as biofertilizers are prokaryotes. Name the taxonomic group they come under. With the help of an…2022
- Farmers are often suggested to use the following organisms in their crop land so as to improve the soil fertility. (i) Rhizobium…2022
- Give an example of viral biocontrol agent. Why are they considered to be desirable when an ecologically sensitive area is being…2022
- Organic farmer use Trichoderma and Baculovirus as biological control agents. Explain.2022
- Study the given diagrams of Biogas plants – 'A' and 'B' and answer the questions that follow: Which one of the two biogas plants…2022
- What are flocs? State their role in biological treatment of sewage.2022
- Different species belonging to genus Trichoderma are useful to humans as well as to plants. Justify their roles by giving one…2022
- Study the given diagram of Sewage Treatment Plant (S.T.P.) and answer the questions that follow: S.T.P. (Sewage Treatment Plant)…2022
- Bacillus thuringiensis plays an important role in Integrated Pest Management strategy. Explain how. Name any two crops that are…2022
- Enumerate the main sources of bio-fertilisers giving one example of each.2022
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