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Microbes in Human Welfare PYQs (previous year questions) for CBSE Class 12: Microbes in Human Welfare (Biology) had 20 questions across the 50 official CBSE Class 12 papers we tagged (2016–2026), and appeared in 10 of them. Asked in 10 of 10 years. The concepts asked in the most papers: Sewage Treatment, Biocontrol Agents, Microbes in Household Products.
Year-wise question count
Asked in 10 of 10 years.
Most-asked concepts
Sorted by the number of papers a concept appeared in.
| Concept | Questions | Papers | Years |
|---|---|---|---|
| Biocontrol Agents | 6 | 5 | 2025, 2022, 2020, 2018, 2016 |
| Sewage Treatment | 6 | 5 | 2026, 2023, 2022, 2019, 2017 |
| Microbes in Household Products | 3 | 3 | 2024, 2020, 2019 |
| Biofertilisers | 2 | 2 | 2022, 2018 |
| Industrial Microbes | 2 | 2 | 2019, 2017 |
| Organic Farming | 1 | 1 | 2022 |
How to practise Microbes in Human Welfare PYQs
- Start with the concepts at the top of the table. They have come back the most.
- Solve one year’s Microbes in Human Welfare questions from the official PDF against the clock, then check the answer listed below.
- Log every miss as a concept gap, a calculation slip or a misread. Each needs a different fix.
- Once a concept is clean in two papers, move to the next. Then sit a full paper from the year pages.
Questions by year
Each line gives the question number and paper, type, concept, our one-line summary, with a link to the official PDF.
CBSE Class 122026
- Q.15 (Biology (57/1/1)) · Assertion-Reason · Sewage Treatment: Nature and role of flocs in secondary sewage treatment PDF
CBSE Class 122025
- Q.3 (Biology (57/1/1)) · Matching · Biocontrol Agents: Match ladybird, mycorrhiza, biocontrol and biogas with organisms PDF
CBSE Class 122024
- Q.8 (Biology (57/1/1)) · MCQ · Microbes in Household Products: Category of bacteria to which curd-setting Lactobacillus belongs PDF
CBSE Class 122023
CBSE Class 122022
- Q.2 (Biology Term 2 (57/1/1)) · Short answer · Sewage Treatment: Effect of agitation and aeration on sewage in the aeration tank PDF
- Q.3 (Biology Term 2 (57/1/1)) · Short answer · Biocontrol Agents: A viral biocontrol agent and why it suits ecologically sensitive areas PDF
- Q.10 (Biology Term 2 (57/1/1)) · Short answer · Biofertilisers: Main sources of biofertilisers with an example of each PDF
- Q.11 (Biology Term 2 (57/1/1)) · Short answer · Organic Farming: Action plan of organic farmers based on biodiversity aiding crop health PDF
CBSE Class 122020
CBSE Class 122019
- Q.4 (Biology (57/1/1)) · Very short answer · Sewage Treatment: What flocs are in secondary sewage treatment PDF
- Q.18 (Biology (57/1/1)) · Short answer · Microbes in Household Products: Bacteria that set curd, the process and another benefit PDF
- Q.20 (Biology (57/1/1)) · Short answer · Industrial Microbes: Match microbes with products; why Swiss cheese has holes PDF
CBSE Class 122018
CBSE Class 122017
CBSE Class 122016
Other Biology chapters
- Reproduction in Organisms PYQs
- Sexual Reproduction in Flowering Plants PYQs
- Human Reproduction PYQs
- Reproductive Health PYQs
- Principles of Inheritance and Variation PYQs
- Molecular Basis of Inheritance PYQs
- Evolution PYQs
- Human Health and Disease PYQs
- Strategies for Enhancement in Food Production PYQs
- Biotechnology: Principles and Processes PYQs
- Biotechnology and its Applications PYQs
- Organisms and Populations PYQs
- Ecosystem PYQs
- Biodiversity and Conservation PYQs
- Environmental Issues PYQs
FAQ
How many Microbes in Human Welfare questions come in CBSE Class 12?
In the official papers we tagged: 1 in 2026, 1 in 2025, 1 in 2024, 2 in 2023, 4 in 2022, 2 in 2020, 3 in 2019, 2 in 2018, 2 in 2017 and 2 in 2016. That is 20 questions in all, about 7% of Biology.
Which Microbes in Human Welfare topics repeat in CBSE Class 12?
Asked in the most papers: Sewage Treatment, Biocontrol Agents, Microbes in Household Products. The concept table lists every one with its count.
Are these official CBSE Class 12 questions?
Yes. Every question is from an official CBSE Class 12 paper hosted on our year pages. The one-line summaries are ours; open the PDF linked beside each question for the full text.