{"id":4115,"date":"2026-04-01T06:38:22","date_gmt":"2026-04-01T06:38:22","guid":{"rendered":"https:\/\/ksquareinstitute.in\/blog\/?p=4115"},"modified":"2026-04-03T12:59:28","modified_gmt":"2026-04-03T12:59:28","slug":"microbes-in-human-welfare-class-12-notes","status":"publish","type":"post","link":"https:\/\/ksquareinstitute.in\/blog\/microbes-in-human-welfare-class-12-notes\/","title":{"rendered":"Microbes in Human Welfare Class 12: Ultimate NEET Revision Guide"},"content":{"rendered":"\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n    <link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n    <link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n    <link href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300..600;1,9..40,300..600&#038;family=JetBrains+Mono:wght@400;500;700&#038;family=Plus+Jakarta+Sans:wght@400;600;700;800&#038;display=swap\" rel=\"stylesheet\">\n    <style>\n        :root {\n            --accent: #e8600a;\n            --accent-light: #fff3ec;\n            --accent-mid: #fde3cc;\n            --dark: #111827;\n            --text: #1a1a1a;\n            --text-muted: #4b5563;\n            --border: #e5e7eb;\n            --green-bg: #f0fdf4;\n            --green-border: #16a34a;\n            --blue-bg: #eff6ff;\n            --blue-border: #3b82f6;\n        }\n\n        * { box-sizing: border-box; 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color: white; display: inline-flex; align-items: center; gap: 10px; padding: 12px 24px; border-radius: 8px; text-decoration: none; font-weight: 600; margin-top: 20px; }\n    <\/style>\n<\/head>\n<body>\n\n<div class=\"content-wrapper\">\n    <div class=\"container\">\n\n        <h2><div class=\"badge\">01<\/div><span>Chapter Overview: Microbes in Human Welfare class 12<\/span><\/h2>\n        \n\n        <p>Mastering the content of <strong>microbes in human welfare class 12<\/strong> is essential for every medical aspirant. While microbes are often associated with diseases, they play an incredibly positive and indispensable role in human life. From the curd you eat for breakfast to the life-saving antibiotics produced in massive industrial fermenters, microorganisms are our unseen partners in survival. For NEET, this chapter is high-yield, focusing on specific microbe-product mappings and the environmental mechanics of sewage treatment. In this guide, we provide a structured analysis of how bacteria, fungi, and viruses contribute to household, industrial, and ecological welfare.<\/p>\n\n        <p>Microbes are ubiquitous\u2014they are found in soil, water, air, and even within our own bodies. They include a diverse range of organisms like bacteria, fungi, protozoa, and certain microscopic algae. Understanding the <strong>microbes in human welfare class 12<\/strong> syllabus involves shifting from a &#8220;pathogen-only&#8221; mindset to recognizing these organisms as biological tools for sustainable development. Let&#8217;s explore the various sectors where microbes dominate.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">BENEFICIAL ROLE<\/span>\n                Microbes facilitate fermentation, nitrogen fixation, waste decomposition, and the production of bioactive molecules.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">INDUSTRIAL SCALE<\/span>\n                Utilization of microbes in large vessels called bioreactors or fermenters to produce chemicals and medicines.\n            <\/div>\n        <\/div>\n\n        <h2><div class=\"badge\">02<\/div><span>Microbes in Household Products<\/span><\/h2>\n        <p>The use of microorganisms in food preparation is one of the oldest human technologies. In your <strong>microbes in human welfare class 12<\/strong> study, memorizing the specific scientific names of these household heroes is critical for quick scoring.<\/p>\n\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Product<\/th>\n                        <th>Microorganism Involved<\/th>\n                        <th>Biological Contribution<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>Curd<\/td>\n                        <td><em>Lactobacillus<\/em> (LAB)<\/td>\n                        <td>Increases Vitamin B<sub>12<\/sub>; inhibits gut pathogens.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Bread<\/td>\n                        <td><em>Saccharomyces cerevisiae<\/em><\/td>\n                        <td>Fermentation releases CO<sub>2<\/sub> making bread fluffy.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Cheese (Swiss)<\/td>\n                        <td><em>Propionibacterium sharmanii<\/em><\/td>\n                        <td>Large holes due to high CO<sub>2<\/sub> production.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Toddy<\/td>\n                        <td>Natural Yeast<\/td>\n                        <td>Fermentation of palm sap (South Indian drink).<\/td>\n                    <\/tr>\n                <\/tbody>\n            <\/table>\n        <\/div>\n\n        <div class=\"callout tip\">\n            <div class=\"callout-pill\">TIP<\/div>\n            Lactic Acid Bacteria (LAB) not only convert lactose into lactic acid to coagulate milk protein but also improve the nutritional quality of curd by enriching it with <strong>Vitamin B<sub>12<\/sub><\/strong>.\n        <\/div>\n\n        <!-- Promotional Banner 1 -->\n        <a href=\"https:\/\/courses.ksquare.co.in\/new-courses\/3-mission-180-neet-physics-rankers-batch\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" style=\"display:block; margin-bottom:40px;\">\n          <img decoding=\"async\" src=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/03\/Course-Poromo-Banner-scaled.png\" alt=\"Mission 180 NEET Physics Rankers Batch - KSquare Career Institute\" style=\"width:100%; height:auto; border-radius:10px; display:block;\">\n        <\/a>\n\n        <h2><div class=\"badge\">03<\/div><span>Microbes in Industrial Products<\/span><\/h2>\n        <p>Industries harness microbial metabolism to produce a wide array of high-value products. For any <strong>microbes in human welfare class 12<\/strong> revision, focus on the bio-active molecules\u2014these are frequent targets for &#8220;match the following&#8221; NEET questions.<\/p>\n\n        <h3>1. Fermented Beverages<\/h3>\n        <p>Brewer&#8217;s yeast (<em>Saccharomyces cerevisiae<\/em>) is used for fermenting malted cereals and fruit juices to produce ethanol. Depending on the raw material and the processing method (with or without distillation), different types of alcoholic drinks are obtained.<\/p>\n\n        <h3>2. Antibiotics and Bioactive Molecules<\/h3>\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">KEY BIOACTIVE MOLECULES<\/span>\n            <div class=\"formula-dark-content\">\n                Cyclosporin A: Immunosuppressant (<em>Trichoderma polysporum<\/em>) <br>\n                Statins: Cholesterol lowering agents (<em>Monascus purpureus<\/em>)\n            <\/div>\n        <\/div>\n\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Chemical Produced<\/th>\n                        <th>Source Organism<\/th>\n                        <th>Nature<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>Citric Acid<\/td>\n                        <td><em>Aspergillus niger<\/em><\/td>\n                        <td>Fungus<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Acetic Acid<\/td>\n                        <td><em>Acetobacter aceti<\/em><\/td>\n                        <td>Bacterium<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Butyric Acid<\/td>\n                        <td><em>Clostridium butylicum<\/em><\/td>\n                        <td>Bacterium<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Streptokinase<\/td>\n                        <td><em>Streptococcus<\/em><\/td>\n                        <td>Clot Buster (for heart patients)<\/td>\n                    <\/tr>\n                <\/tbody>\n            <\/table>\n        <\/div>\n\n        <h2><div class=\"badge\">04<\/div><span>Microbes in Sewage Treatment<\/span><\/h2>\n        <p>Large quantities of municipal waste-water (sewage) are generated daily. Treatment in Sewage Treatment Plants (STPs) is mandatory before disposal. The <strong>microbes in human welfare class 12<\/strong> chapter details a two-stage process.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">PRIMARY TREATMENT<\/span>\n                A physical process involving sequential filtration and sedimentation to remove floating debris and grit.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">SECONDARY TREATMENT<\/span>\n                A biological process where aerobic microbes consume organic matter in aeration tanks, forming **Flocs**.\n            <\/div>\n        <\/div>\n\n        <div class=\"formula-orange\">\n            <span class=\"formula-orange-label\">BOD DEFINITION<\/span>\n            <div class=\"formula-orange-content\">Biological Oxygen Demand: Oxygen required by microbes to oxidize all organic matter in 1L of water.<\/div>\n            <p style=\"font-size: 0.85rem; margin-top: 5px;\">(Higher BOD = Higher Polluting Potential.)<\/p>\n        <\/div>\n\n        <div class=\"callout warning\">\n            <div class=\"callout-pill\">WARN<\/div>\n            <strong>Activated Sludge:<\/strong> Once BOD is reduced, flocs are allowed to sediment. This sediment is called activated sludge. A small part is recycled as inoculum, and the rest is sent to anaerobic sludge digesters.\n        <\/div>\n\n        <h2><div class=\"badge\">05<\/div><span>Microbes in Biogas Production<\/span><\/h2>\n        <p>Biogas is a mixture of gases produced by microbial activity. Certain bacteria, which grow anaerobically on cellulosic material, produce large amounts of methane along with CO<sub>2<\/sub> and H<sub>2<\/sub>. These are called **Methanogens**.<\/p>\n\n        <ul>\n            <li><strong>Organism:<\/strong> <em>Methanobacterium<\/em>, found in anaerobic sludge and the rumen of cattle.<\/li>\n            <li><strong>Process:<\/strong> Cattle dung (gobar) is rich in these bacteria, making it an ideal substrate for rural biogas plants.<\/li>\n            <li><strong>Structure:<\/strong> A typical plant consists of a concrete tank (digester), a floating cover (gas holder), and outlet pipes for slurry and gas.<\/li>\n        <\/ul>\n\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">BIOGAS COMPOSITION<\/span>\n            <div class=\"formula-dark-content\">Methane (CH<sub>4<\/sub>) + Carbon Dioxide (CO<sub>2<\/sub>) + Hydrogen Sulfide (H<sub>2<\/sub>S)<\/div>\n        <\/div>\n\n        <!-- Promotional Banner 2 -->\n        <a href=\"https:\/\/ksquareinstitute.in\/neet-2026-rank-predictor\/\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" style=\"display:block; margin-bottom:40px;\">\n          <img decoding=\"async\" src=\"https:\/\/ksquareinstitute.in\/blog\/wp-content\/uploads\/2026\/03\/neet-2026-college-and-rank-predictor-scaled.png\" alt=\"NEET 2026 Rank Predictor - KSquare Career Institute\" style=\"width:100%; height:auto; border-radius:10px; display:block;\">\n        <\/a>\n\n        <h2><div class=\"badge\">06<\/div><span>Microbes as Biocontrol Agents<\/span><\/h2>\n        <p>Biocontrol refers to the use of biological methods for controlling plant diseases and pests. This is a sustainable alternative to chemical insecticides and pesticides in the <strong>microbes in human welfare class 12<\/strong> curriculum.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">Bacillus thuringiensis (Bt)<\/span>\n                Bacteria used to control butterfly caterpillars. It produces a toxin that kills the insect upon ingestion.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">Trichoderma<\/span>\n                Free-living fungi that are very common in root ecosystems. They act against several plant pathogens.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">Baculoviruses<\/span>\n                Pathogens that attack insects. Most used for biocontrol belong to the genus <em>Nucleopolyhedrovirus<\/em>.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">Ladybird &#038; Dragonflies<\/span>\n                Natural predators used to get rid of aphids and mosquitoes, respectively.\n            <\/div>\n        <\/div>\n\n        <h2><div class=\"badge\">07<\/div><span>Microbes as Biofertilizers<\/span><\/h2>\n        <p>Biofertilizers are organisms that enrich the nutrient quality of the soil. With the increasing cost and pollution caused by chemical fertilizers, biofertilizers are the future of organic farming. Mastery of these symbionts is vital for <strong>microbes in human welfare class 12<\/strong> notes.<\/p>\n        \n        <ul>\n            <li><strong>Rhizobium:<\/strong> Symbiotic bacteria in root nodules of legumes that fix atmospheric nitrogen.<\/li>\n            <li><strong>Azospirillum &#038; Azotobacter:<\/strong> Free-living bacteria in the soil that also fix nitrogen.<\/li>\n            <li><strong>Mycorrhiza (Glomus):<\/strong> Fungal association with plant roots. The fungus absorbs phosphorus from soil and provides resistance to root-borne pathogens.<\/li>\n            <li><strong>Cyanobacteria:<\/strong> Autotrophic microbes like <em>Anabaena<\/em> and <em>Nostoc<\/em>. In paddy fields, they serve as an important biofertilizer.<\/li>\n        <\/ul>\n\n        <div class=\"internal-links\">\n            <span class=\"internal-links-title\">ENHANCE YOUR NEET PREPARATION<\/span>\n            <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-physics-survival-kit-2026\/\">NEET Physics Survival Kit 2026<\/a>\n            <a href=\"https:\/\/ksquareinstitute.in\/blog\/organic-chemistry-strategy-neet\/\">Organic Chemistry Strategy for NEET<\/a>\n            <a href=\"https:\/\/ksquareinstitute.in\/blog\/neet-biology-tricks-for-exams\/\">Biology Mnemonics &#038; Tricks<\/a>\n            <a href=\"https:\/\/ksquareinstitute.in\/blog\/score-340-in-neet-biology\/\">How to Score 340 in NEET Biology<\/a>\n            <a href=\"https:\/\/ksquareinstitute.in\/blog\/top-10-tricky-neet-biology-diagrams\/\">Top 10 Tricky Biology Diagrams<\/a>\n        <\/div>\n\n        <div class=\"revision-box\">\n            <h3>Quick Revision Summary<\/h3>\n            <ul>\n                <li><strong>LAB:<\/strong> Converts milk to curd, improves Vit B<sub>12<\/sub>.<\/li>\n                <li><strong>Yeast:<\/strong> <em>Saccharomyces cerevisiae<\/em> (Baker&#8217;s\/Brewer&#8217;s yeast).<\/li>\n                <li><strong>Penicillin:<\/strong> First antibiotic discovered by Alexander Fleming from <em>Penicillium notatum<\/em>.<\/li>\n                <li><strong>Statins:<\/strong> Competitive inhibitor for HMG-CoA reductase (cholesterol lowering).<\/li>\n                <li><strong>Secondary Treatment:<\/strong> Biological process involving Flocs and Aeration.<\/li>\n                <li><strong>BOD:<\/strong> Indicator of the amount of organic waste in water.<\/li>\n                <li><strong>Methanogens:<\/strong> Produce Biogas (predominantly CH<sub>4<\/sub>) in anaerobic digesters.<\/li>\n                <li><strong>Bt Cotton:<\/strong> Genetically engineered plant using <em>B. thuringiensis<\/em> genes.<\/li>\n                <li><strong>Cyanobacteria:<\/strong> Fix atmospheric Nitrogen in paddy fields.<\/li>\n                <li><strong>IPM:<\/strong> Integrated Pest Management utilizes target-specific biocontrol agents.<\/li>\n            <\/ul>\n            <a href=\"#\" class=\"download-btn\" rel=\"nofollow noopener noreferrer\">\n                <span>Download Microbes Summary PDF<\/span>\n            <\/a>\n        <\/div>\n\n        <h2><div class=\"badge\">08<\/div><span>Frequently Asked Questions<\/span><\/h2>\n        <div class=\"faq-container\">\n            <details>\n                <summary>\n                    <span>What is the difference between Primary and Secondary sewage treatment?<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">Primary treatment is a physical process that removes large solids and grit through filtration and sedimentation. Secondary treatment is a biological process where aerobic bacteria (in flocs) break down the organic matter in the water to reduce its BOD.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Why is BOD important in determining water quality?<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">BOD measures the rate of oxygen uptake by microorganisms in a sample of water. A high BOD indicates that the water is heavily polluted with organic waste, as microbes are consuming lots of oxygen to decompose it. As treatment progresses, BOD decreases.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>How do statins lower blood cholesterol levels?<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">Statins, produced by the yeast <em>Monascus purpureus<\/em>, act by competitively inhibiting the enzyme responsible for the synthesis of cholesterol in the liver. This reduction in enzyme activity results in lower levels of cholesterol in the blood.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What are &#8220;Flocs&#8221; in the context of sewage treatment?<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">Flocs are masses of bacteria associated with fungal filaments to form mesh-like structures. During the aeration phase of secondary treatment, these flocs consume the major part of the organic matter in the effluent, significantly reducing the BOD.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Explain the role of Methanogens in a biogas plant.<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">Methanogens (like <em>Methanobacterium<\/em>) grow anaerobically on cellulosic materials in the digester tank. They decompose the organic waste (slurry) to produce a mixture of gases, primarily methane (CH<sub>4<\/sub>), which is used as fuel.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What are the advantages of using Biofertilizers over chemical ones?<\/span>\n                    <div class=\"toggle-icon\">\n                        <svg viewBox=\"0 0 24 24\"><path class=\"plus-path\" d=\"M12 5v14M5 12h14\"\/><path class=\"minus-path\" d=\"M5 12h14\"\/><\/svg>\n                    <\/div>\n                <\/summary>\n                <div class=\"faq-answer\">Biofertilizers are cost-effective, eco-friendly, and do not cause soil or water pollution. They improve soil texture, increase nutrient availability (especially nitrogen and phosphorus), and enhance the plant&#8217;s resistance to environmental stress and pathogens.<\/div>\n            <\/details>\n        <\/div>\n\n        <div class=\"cta-section\">\n            <h2>Micro-manage Your NEET Success with KSquare<\/h2>\n            <p>Mastering <strong>microbes in human welfare class 12<\/strong> content is your gateway to medical school. Join KSquare Institute&#8217;s Mission 180 Rankers Batch for expert-led biology walkthroughs, high-yield product tables, and personalized mentorship to ensure you dominate NEET Biology.<\/p>\n            <div class=\"cta-buttons\">\n                <a href=\"https:\/\/courses.ksquare.co.in\/new-courses\/3-mission-180-neet-physics-rankers-batch\" class=\"btn btn-white\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">Join Rankers Batch<\/a>\n                <a href=\"https:\/\/ksquareinstitute.in\/free-study-material\/\" class=\"btn btn-outline\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">Get Free Study Material<\/a>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<\/body>\n<\/html>\n\n\n\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n  <meta charset=\"UTF-8\">\n  <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n  <title>Table of Contents \u2014 Biology Class 12<\/title>\n  \n  <!-- Google Fonts Import -->\n  <link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n  <link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n  <link href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,100..1000;1,9..40,100..1000&#038;family=Plus+Jakarta+Sans:ital,wght@0,200..800;1,200..800&#038;display=swap\" rel=\"stylesheet\">\n  \n  <style>\n    \/* Scoped wrapper using a unique ID (#biology-toc-wrapper).\n       Ensures zero CSS leakage and full width edge-to-edge layout.\n    *\/\n    #biology-toc-wrapper {\n      font-family: 'DM Sans', sans-serif;\n      width: 100%;\n      margin: 0;\n      padding: 60px 0;\n      color: #111;\n      background: #fff;\n      -webkit-font-smoothing: antialiased;\n    }\n\n    #biology-toc-wrapper .container-inner {\n      width: 100%;\n      margin: 0 auto;\n      padding: 0; \n    }\n\n    #biology-toc-wrapper h1 {\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 0.85rem;\n      font-weight: 700;\n      color: #71717a;\n      margin: 0 0 8px;\n      letter-spacing: 0.1em;\n      text-transform: uppercase;\n      padding-left: 16px; \n    }\n\n    #biology-toc-wrapper h2 {\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 2.25rem;\n      font-weight: 800;\n      margin: 0 0 48px;\n      letter-spacing: -0.02em;\n      color: #09090b;\n      padding-left: 16px;\n    }\n\n    #biology-toc-wrapper table {\n      width: 100%;\n      border-collapse: collapse;\n      border-spacing: 0;\n      border-top: 1px solid #e4e4e7;\n      border-bottom: 1px solid #e4e4e7;\n    }\n\n    #biology-toc-wrapper tr {\n      border-bottom: 1px solid #e4e4e7;\n      transition: all 0.2s ease;\n    }\n\n    #biology-toc-wrapper tr:hover {\n      background-color: #f8fafc;\n    }\n\n    #biology-toc-wrapper tr:last-child {\n      border-bottom: none;\n    }\n\n    #biology-toc-wrapper td {\n      padding: 24px 16px;\n      vertical-align: middle;\n      font-size: 1.05rem;\n      font-weight: 500;\n      border-right: 1px solid #e4e4e7;\n    }\n\n    #biology-toc-wrapper td:last-child {\n      border-right: none;\n    }\n\n    \/* Column 1: Index Numbers *\/\n    #biology-toc-wrapper td:first-child {\n      color: #a1a1aa;\n      font-size: 0.9rem;\n      width: 70px;\n      font-weight: 400;\n      font-variant-numeric: tabular-nums;\n      text-align: center;\n      padding-left: 10px;\n    }\n\n    \/* Column 2: Chapter Titles *\/\n    #biology-toc-wrapper td:nth-child(2) {\n      padding-left: 32px; \n      color: #18181b;\n    }\n\n    \/* Column 3: Action Button *\/\n    #biology-toc-wrapper td:last-child {\n      text-align: right;\n      width: 180px;\n      padding-right: 24px; \n    }\n\n    \/* Premium Button Styling *\/\n    #biology-toc-wrapper a.go {\n      display: inline-block;\n      font-family: 'Plus Jakarta Sans', sans-serif;\n      font-size: 0.75rem;\n      font-weight: 800;\n      padding: 12px 24px;\n      border: 1.5px solid #18181b;\n      border-radius: 8px;\n      color: #18181b;\n      text-decoration: none;\n      letter-spacing: 0.05em;\n      text-transform: uppercase;\n      transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);\n      white-space: nowrap;\n    }\n\n    #biology-toc-wrapper a.go:hover {\n      background: #18181b;\n      color: #ffffff;\n      transform: translateY(-2px);\n      box-shadow: 0 4px 12px rgba(24, 24, 27, 0.15);\n    }\n\n    \/* Responsive adjustments *\/\n    @media (max-width: 768px) {\n      #biology-toc-wrapper h2 {\n        font-size: 1.75rem;\n        margin-bottom: 32px;\n        padding-left: 12px;\n      }\n      #biology-toc-wrapper td {\n        padding: 18px 12px;\n        font-size: 0.95rem;\n      }\n      #biology-toc-wrapper td:nth-child(2) {\n        padding-left: 16px;\n      }\n    }\n  <\/style>\n<\/head>\n<body>\n\n<div id=\"biology-toc-wrapper\">\n  <div class=\"container-inner\">\n    <h1>Table of Contents<\/h1>\n    <h2>Biology &mdash; Class 12<\/h2>\n    \n    <table>\n      <tr><td>01<\/td><td>Sexual Reproduction in Flowering Plants<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/sexual-reproduction-in-flowering-plants-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>02<\/td><td>Human Reproduction<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/human-reproduction-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>03<\/td><td>Reproductive Health<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/reproductive-health-class-12-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>04<\/td><td>Principles of Inheritance and Variation<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/principles-of-inheritance-and-variation-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>05<\/td><td>Molecular Basis of Inheritance<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/molecular-basis-of-inheritance-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>06<\/td><td>Evolution<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/evolution-class-12-notes-pdf-download\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>07<\/td><td>Human Health and Disease<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/human-health-and-disease-class-12-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>08<\/td><td>Microbes in Human Welfare<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/microbes-in-human-welfare-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>09<\/td><td>Biotechnology: Principles and Processes<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/biotechnology-principles-and-processes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>10<\/td><td>Biotechnology and its Applications<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/biotechnology-and-its-applications-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>11<\/td><td>Organisms and Populations<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/organisms-and-populations-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>12<\/td><td>Ecosystem<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/ecosystem-class-12-notes-pdf\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n      <tr><td>13<\/td><td>Biodiversity and Conservation<\/td><td><a class=\"go\" href=\"https:\/\/ksquareinstitute.in\/blog\/biodiversity-and-conservation-class-12-notes\" target=\"_blank\">Go to page<\/a><\/td><\/tr>\n    <\/table>\n  <\/div>\n<\/div>\n\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"<p>01 Chapter Overview: Microbes in Human Welfare class 12 Mastering the content of microbes in human welfare class 12 is essential for every medical aspirant. While microbes are often associated with diseases, they play an incredibly positive and indispensable role in human life. From the curd you eat for breakfast to the life-saving antibiotics produced [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[127],"tags":[533,531,538,537,529,530,534,536,532,535],"class_list":["post-4115","post","type-post","status-publish","format-standard","hentry","category-free-study-material","tag-biology-notes-class-12","tag-class-12-biology-chapter-10","tag-class-12-biology-revision-notes","tag-microbes-chapter-summary","tag-microbes-in-human-welfare-class-12","tag-microbes-in-human-welfare-notes","tag-microbes-in-human-welfare-pdf","tag-microbes-uses-in-human-welfare","tag-ncert-microbes-in-human-welfare","tag-neet-biology-microbes"],"blocksy_meta":{"page_structure_type":"type-1","styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":6}},"_links":{"self":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4115","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/comments?post=4115"}],"version-history":[{"count":2,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4115\/revisions"}],"predecessor-version":[{"id":4279,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4115\/revisions\/4279"}],"wp:attachment":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media?parent=4115"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/categories?post=4115"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/tags?post=4115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}