{"id":4107,"date":"2026-04-01T05:47:12","date_gmt":"2026-04-01T05:47:12","guid":{"rendered":"https:\/\/ksquareinstitute.in\/blog\/?p=4107"},"modified":"2026-04-03T12:58:35","modified_gmt":"2026-04-03T12:58:35","slug":"molecular-basis-of-inheritance-class-12-notes","status":"publish","type":"post","link":"https:\/\/ksquareinstitute.in\/blog\/molecular-basis-of-inheritance-class-12-notes\/","title":{"rendered":"Molecular Basis of Inheritance Class 12: The Ultimate NEET Study 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>Introduction to the Molecular Basis of Inheritance Class 12<\/span><\/h2>\n        \n\n        <p>Mastering the <strong>molecular basis of inheritance class 12<\/strong> is essential for any medical aspirant. While genetics deals with the patterns of inheritance, molecular biology digs deep into the actual molecules\u2014DNA and RNA\u2014that carry the blueprints of life. In NEET, this chapter is high-yield, consistently providing 5-6 questions on everything from the historical experiments of Griffith to the modern techniques of DNA fingerprinting. This guide provides a conceptual deep dive into how information flows from the genome to the proteome.<\/p>\n\n        <p>At its core, the molecular basis of inheritance class 12 focuses on the &#8220;Central Dogma&#8221; of biology: DNA makes RNA, and RNA makes Protein. For a student, the challenge is to visualize these microscopic processes. Understanding the chemical structure of nucleotides and the mechanical precision of replication is the first step toward clinical excellence.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">GENETIC MATERIAL<\/span>\n                Substances that store and transmit biological information. To be effective, it must replicate accurately and remain stable.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">CENTRAL DOGMA<\/span>\n                DNA &rarr; (Transcription) &rarr; RNA &rarr; (Translation) &rarr; Protein. Proposed by Francis Crick.\n            <\/div>\n        <\/div>\n\n        <h2><div class=\"badge\">02<\/div><span>Proving DNA as the Genetic Material<\/span><\/h2>\n        <p>Before the mid-20th century, scientists debated whether proteins or nucleic acids were the carriers of inheritance. Three landmark experiments detailed in the <strong>molecular basis of inheritance class 12<\/strong> syllabus settled this debate.<\/p>\n\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Experiment<\/th>\n                        <th>Year<\/th>\n                        <th>Key Discovery<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>Frederick Griffith<\/td>\n                        <td>1928<\/td>\n                        <td>Transforming Principle: Non-virulent R strain becomes virulent S strain when exposed to heat-killed S strain.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Avery, MacLeod, McCarty<\/td>\n                        <td>1944<\/td>\n                        <td>DNA is the Transforming Principle: Proved that only DNA-digesting enzymes (DNase) inhibited transformation.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Hershey and Chase<\/td>\n                        <td>1952<\/td>\n                        <td>Unequivocal Proof: Used <sup>35<\/sup>S (Protein) and <sup>32<\/sup>P (DNA) bacteriophages to prove DNA enters the host cell.<\/td>\n                    <\/tr>\n                <\/tbody>\n            <\/table>\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>Structure and Packaging of DNA<\/span><\/h2>\n        <p>DNA is a long polymer of deoxyribonucleotides. Its double-helical structure was proposed by Watson and Crick in 1953 based on X-ray diffraction data from Maurice Wilkins and Rosalind Franklin. This is a fundamental part of <strong>molecular basis of inheritance class 12<\/strong> studies.<\/p>\n\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">CHARGAFF&#8217;S RULE<\/span>\n            <div class=\"formula-dark-content\">\n                A = T (2 Hydrogen Bonds) <br>\n                G &equiv; C (3 Hydrogen Bonds) <br>\n                [Purines] = [Pyrimidines]\n            <\/div>\n        <\/div>\n\n        <h3>Packaging of DNA Helix<\/h3>\n        <p>Human DNA is about 2.2 meters long, yet it fits inside a microscopic nucleus. This is achieved by wrapping DNA around basic proteins called **Histones** to form nucleosomes. A string of nucleosomes forms chromatin, which further condenses into chromosomes.<\/p>\n        <ul>\n            <li><strong>Euchromatin:<\/strong> Loosely packed, stains light, transcriptionally active.<\/li>\n            <li><strong>Heterochromatin:<\/strong> Densely packed, stains dark, transcriptionally inactive.<\/li>\n        <\/ul>\n\n        <h2><div class=\"badge\">04<\/div><span>DNA Replication: The Semi-Conservative Model<\/span><\/h2>\n        <p>Meselson and Stahl provided experimental proof using heavy nitrogen (<sup>15<\/sup>N) that DNA replication is semi-conservative\u2014each daughter molecule retains one parental strand and one newly synthesized strand. This is a common numerical target in <strong>molecular basis of inheritance class 12<\/strong> MCQ sets.<\/p>\n\n        <div class=\"callout tip\">\n            <div class=\"callout-pill\">TIP<\/div>\n            DNA Polymerase can only add nucleotides in the <strong>5&#8242; &rarr; 3&#8242; direction<\/strong>. This creates the &#8220;Leading Strand&#8221; (continuous) and the &#8220;Lagging Strand&#8221; (discontinuous fragments called Okazaki fragments).\n        <\/div>\n\n        <h3>Key Enzymes of Replication<\/h3>\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Enzyme<\/th>\n                        <th>Function<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>Helicase<\/td>\n                        <td>Unwinds the double helix at the replication fork.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Primase<\/td>\n                        <td>Synthesizes short RNA primers required for DNA polymerase.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>DNA Polymerase III<\/td>\n                        <td>Main enzyme that adds nucleotides to the new strand.<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>DNA Ligase<\/td>\n                        <td>Joins Okazaki fragments on the lagging strand.<\/td>\n                    <\/tr>\n                <\/tbody>\n            <\/table>\n        <\/div>\n\n        <h2><div class=\"badge\">05<\/div><span>Transcription: Decoding the Message<\/span><\/h2>\n        <p>Transcription is the process of copying genetic information from one strand of DNA into RNA. Unlike replication, only a segment of DNA is copied, and only one strand (the template strand) is used. Understanding the transcription unit is vital for the <strong>molecular basis of inheritance class 12<\/strong> NCERT revision.<\/p>\n\n        <div class=\"formula-orange\">\n            <span class=\"formula-orange-label\">TRANSCRIPTION UNIT<\/span>\n            <div class=\"formula-orange-content\">Promoter + Structural Gene + Terminator<\/div>\n        <\/div>\n\n        <h3>Post-Transcriptional Processing in Eukaryotes<\/h3>\n        <p>The primary transcript (hnRNA) contains both exons (coding) and introns (non-coding). It undergoes three modifications before becoming mature mRNA:<\/p>\n        <ol>\n            <li><strong>Splicing:<\/strong> Removal of introns and joining of exons.<\/li>\n            <li><strong>Capping:<\/strong> Addition of methyl guanosine triphosphate at 5&#8242; end.<\/li>\n            <li><strong>Tailing:<\/strong> Addition of adenylate residues (Poly-A tail) at 3&#8242; end.<\/li>\n        <\/ol>\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>The Genetic Code and Translation<\/span><\/h2>\n        <p>The genetic code is the set of rules by which information encoded in genetic material is translated into proteins. In the <strong>molecular basis of inheritance class 12<\/strong>, the properties of the code are high-yield facts.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">PROPERTIES<\/span>\n                Triplet, Universal, Degenerate (one amino acid coded by many codons), Non-overlapping, and Commaless.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">START\/STOP<\/span>\n                AUG (Methionine) is the start codon. UAA, UAG, and UGA are stop (nonsense) codons.\n            <\/div>\n        <\/div>\n\n        <h3>Translation Mechanism<\/h3>\n        <p>Occurs on ribosomes. Amino acids are activated by ATP and linked to their specific tRNA (charging). tRNA acts as an adapter molecule, recognizing the codon on mRNA via its anticodon loop and bringing the corresponding amino acid.<\/p>\n\n        <h2><div class=\"badge\">07<\/div><span>Regulation of Gene Expression: Lac Operon<\/span><\/h2>\n        <p>Gene regulation allows organisms to respond to environmental changes. Jacob and Monod proposed the <strong>Lac Operon<\/strong> model in <em>E. coli<\/em>. It is an inducible system that is switched &#8220;ON&#8221; only in the presence of lactose.<\/p>\n        \n        <ul>\n            <li><strong>i gene:<\/strong> Produces the repressor protein.<\/li>\n            <li><strong>z gene:<\/strong> Codes for Beta-galactosidase (breaks lactose).<\/li>\n            <li><strong>y gene:<\/strong> Codes for Permease (increases cell permeability).<\/li>\n            <li><strong>a gene:<\/strong> Codes for Transacetylase.<\/li>\n        <\/ul>\n\n        <div class=\"callout warning\">\n            <div class=\"callout-pill\">WARN<\/div>\n            In the absence of an inducer (lactose), the repressor binds to the <strong>operator<\/strong> region and prevents RNA polymerase from transcribing the structural genes.\n        <\/div>\n\n        <h2><div class=\"badge\">08<\/div><span>Human Genome Project and DNA Fingerprinting<\/span><\/h2>\n        <p>The Human Genome Project (HGP) was a 13-year mega project (1990-2003) to sequence all 3 billion base pairs of the human genome. DNA Fingerprinting, developed by Alec Jeffreys, uses **VNTRs** (Variable Number Tandem Repeats) to identify individuals.<\/p>\n\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">DNA POLYMORPHISM<\/span>\n            <div class=\"formula-dark-content\">Inheritable mutations at high frequency in a population; forms the basis of DNA fingerprinting.<\/div>\n        <\/div>\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            <a href=\"https:\/\/ksquareinstitute.in\/free-study-material\/\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">Free Study Material<\/a>\n        <\/div>\n\n        <div class=\"revision-box\">\n            <h3>Quick Revision Summary<\/h3>\n            <ul>\n                <li><strong>Griffith (1928):<\/strong> Transformation. <strong>Hershey-Chase (1952):<\/strong> DNA is the genetic material.<\/li>\n                <li><strong>Nucleoside:<\/strong> Base + Sugar. <strong>Nucleotide:<\/strong> Base + Sugar + Phosphate.<\/li>\n                <li><strong>DNA Pitch:<\/strong> 3.4 nm per turn with 10 base pairs.<\/li>\n                <li><strong>Replication Fork:<\/strong> Direction of synthesis is 5&#8242; &rarr; 3&#8242;.<\/li>\n                <li><strong>Promoter:<\/strong> Binding site for RNA polymerase (upstream of structural gene).<\/li>\n                <li><strong>mRNA Processing:<\/strong> Splicing, Capping, Tailing occurs in eukaryotes only.<\/li>\n                <li><strong>AUG:<\/strong> Dual function (Codes for Met and acts as Initiator).<\/li>\n                <li><strong>tRNA:<\/strong> Clover-leaf 2D structure; L-shaped 3D structure.<\/li>\n                <li><strong>Lac Operon:<\/strong> Negatively regulated by a repressor protein.<\/li>\n                <li><strong>HGP:<\/strong> Human genome contains ~3164.7 million nucleotide bases.<\/li>\n            <\/ul>\n            <a href=\"#\" class=\"download-btn\" rel=\"nofollow noopener noreferrer\">\n                <span>Download Molecular Biology PDF<\/span>\n            <\/a>\n        <\/div>\n\n        <h2><div class=\"badge\">09<\/div><span>Frequently Asked Questions<\/span><\/h2>\n        <div class=\"faq-container\">\n            <details>\n                <summary>\n                    <span>Why is DNA a better genetic material than RNA?<\/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\">DNA is more stable because: 1. It is double-stranded. 2. It has deoxyribose sugar (lacks the reactive 2&#8242;-OH group). 3. It contains Thymine instead of Uracil, which is less prone to mutation. RNA is reactive and acts as a catalyst, making it less ideal for long-term storage.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Explain the significance of the &#8220;Degeneracy&#8221; of the genetic code.<\/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\">Degeneracy means that some amino acids are coded by more than one codon (e.g., Leucine has 6 codons). This acts as a protective buffer against point mutations; if one base changes, there is a chance it still codes for the same amino acid (Silent mutation).<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What are Okazaki fragments and why are they formed?<\/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\">DNA polymerase can only synthesize in the 5&#8242; to 3&#8242; direction. On the lagging strand (3&#8242; to 5&#8242; template), the fork opens in the opposite direction of synthesis. Therefore, DNA is made in short, discontinuous pieces called Okazaki fragments, which are later joined by Ligase.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What is the difference between a Template strand and a Coding strand?<\/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\">The Template strand (3&#8242; &rarr; 5&#8242;) acts as a guide for RNA synthesis. The Coding strand (5&#8242; &rarr; 3&#8242;) does not code for anything but has the same sequence as the newly formed RNA (except T is replaced by U). Curiously, IUPAC references the coding strand when describing gene sequences.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>How does DNA fingerprinting work at the molecular level?<\/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\">It targets satellite DNA\u2014regions of non-coding DNA that contain highly repetitive sequences called VNTRs. The number of repeats varies from person to person. By cutting DNA with restriction enzymes and separating fragments by gel electrophoresis, a unique &#8220;barcode&#8221; or fingerprint is generated.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What is the role of the Sigma factor in transcription?<\/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\">In prokaryotes, the RNA polymerase enzyme cannot initiate transcription on its own. The Sigma (&sigma;) factor binds to the enzyme to help it recognize and bind to the promoter region, initiating the process. After initiation, the &sigma; factor dissociates.<\/div>\n            <\/details>\n        <\/div>\n\n        <div class=\"cta-section\">\n            <h2>Master the Code of Life with KSquare<\/h2>\n            <p>Mastering the <strong>molecular basis of inheritance class 12<\/strong> content is your gateway to a perfect score in NEET Biology. Join KSquare Institute&#8217;s Mission 180 Rankers Batch for expert-led molecular animations, diagram-intensive study material, and high-yield mock tests to ensure you secure your medical seat.<\/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 Introduction to the Molecular Basis of Inheritance Class 12 Mastering the molecular basis of inheritance class 12 is essential for any medical aspirant. While genetics deals with the patterns of inheritance, molecular biology digs deep into the actual molecules\u2014DNA and RNA\u2014that carry the blueprints of life. In NEET, this chapter is high-yield, consistently providing [&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":[502,507,501,505,508,500,506,504,492,503],"class_list":["post-4107","post","type-post","status-publish","format-standard","hentry","category-free-study-material","tag-class-12-biology-molecular-basis-of-inheritance","tag-dna-rna-functions-class-12","tag-dna-structure-and-replication-class-12","tag-genetics-class-12-notes","tag-inheritance-chapter-notes","tag-molecular-basis-of-inheritance-class-12","tag-molecular-genetics-notes","tag-ncert-molecular-basis-of-inheritance","tag-neet-biology-genetics","tag-transcription-and-translation-notes"],"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\/4107","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=4107"}],"version-history":[{"count":2,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4107\/revisions"}],"predecessor-version":[{"id":4276,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4107\/revisions\/4276"}],"wp:attachment":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media?parent=4107"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/categories?post=4107"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/tags?post=4107"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}