{"id":4105,"date":"2026-04-01T05:28:03","date_gmt":"2026-04-01T05:28:03","guid":{"rendered":"https:\/\/ksquareinstitute.in\/blog\/?p=4105"},"modified":"2026-04-03T12:58:12","modified_gmt":"2026-04-03T12:58:12","slug":"principles-of-inheritance-and-variation-pdf","status":"publish","type":"post","link":"https:\/\/ksquareinstitute.in\/blog\/principles-of-inheritance-and-variation-pdf\/","title":{"rendered":"Principles of Inheritance and Variation PDF: The 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>Introduction to Genetics and Inheritance<\/span><\/h2>\n        \n\n        <p>Mastering the fundamental concepts of this chapter is essential for any medical aspirant. This comprehensive <strong>principles of inheritance and variation pdf<\/strong> guide provides a high-yield analysis of how traits are passed from parents to offspring and the mechanisms that drive biological diversity. Genetics is the branch of biology that explores inheritance (the process of passing characters) and variation (the degree by which progeny differ from parents). For NEET, this chapter consistently yields 4-5 high-weightage questions, making it a &#8220;must-perfect&#8221; topic for securing a top rank.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">INHERITANCE<\/span>\n                The biological process through which genetic information is transmitted from one generation to the next.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">VARIATION<\/span>\n                Differences in the characteristics of individuals of the same species, providing the raw material for evolution.\n            <\/div>\n        <\/div>\n\n        <h3>Basic Terminology for Genetics<\/h3>\n        <ul>\n            <li><strong>Gene:<\/strong> The functional unit of inheritance (Mendel&#8217;s &#8220;factors&#8221;).<\/li>\n            <li><strong>Allele:<\/strong> Alternative forms of a gene occupying the same locus on homologous chromosomes.<\/li>\n            <li><strong>Genotype:<\/strong> The genetic constitution of an organism (e.g., TT, Tt).<\/li>\n            <li><strong>Phenotype:<\/strong> The observable physical expression of traits (e.g., Tall, Dwarf).<\/li>\n        <\/ul>\n\n        <h2><div class=\"badge\">02<\/div><span>Mendel&#8217;s Experiments with Pea Plants<\/span><\/h2>\n        <p>Gregor Mendel, known as the Father of Genetics, conducted hybridization experiments on garden peas (<em>Pisum sativum<\/em>) for seven years (1856-1863). In your <strong>principles of inheritance and variation pdf<\/strong> study, you must memorize the seven pairs of contrasting traits he selected, such as stem height, seed shape, and flower color.<\/p>\n\n        <div class=\"callout tip\">\n            <div class=\"callout-pill\">TIP<\/div>\n            Mendel&#8217;s success was due to his selection of true-breeding lines and his unique application of statistical analysis and mathematical logic to biological problems\u2014a precursor to modern data analysis.\n        <\/div>\n\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Trait<\/th>\n                        <th>Dominant Expression<\/th>\n                        <th>Recessive Expression<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>Stem Height<\/td>\n                        <td>Tall<\/td>\n                        <td>Dwarf<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Seed Shape<\/td>\n                        <td>Round<\/td>\n                        <td>Wrinkled<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Seed Color<\/td>\n                        <td>Yellow<\/td>\n                        <td>Green<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Flower Position<\/td>\n                        <td>Axial<\/td>\n                        <td>Terminal<\/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>Monohybrid Cross and Mendelian Laws<\/span><\/h2>\n        <p>A cross involving only one pair of contrasting traits is a monohybrid cross. When Mendel crossed tall and dwarf plants, the F<sub>1<\/sub> generation was entirely tall, while the F<sub>2<\/sub> showed both traits. This led to the formulation of two fundamental laws.<\/p>\n\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">MONOHYBRID RATIOS<\/span>\n            <div class=\"formula-dark-content\">\n                Phenotypic Ratio: 3 : 1 <br>\n                Genotypic Ratio: 1 : 2 : 1\n            <\/div>\n        <\/div>\n\n        <h3>1. Law of Dominance<\/h3>\n        <p>Characters are controlled by discrete units called factors (genes) which occur in pairs. In a dissimilar pair, one member dominates (dominant) the other (recessive).<\/p>\n\n        <h3>2. Law of Segregation<\/h3>\n        <p>Alleles do not show any blending and both characters are recovered as such in the F<sub>2<\/sub> generation. During gamete formation, the factors or alleles of a pair segregate such that a gamete receives only one of the two factors. This is also known as the <strong>Law of Purity of Gametes<\/strong>.<\/p>\n\n        <h2><div class=\"badge\">04<\/div><span>Dihybrid Cross: Principles of Inheritance and Variation PDF Guide<\/span><\/h2>\n        <p>A dihybrid cross involves two pairs of contrasting traits simultaneously (e.g., Seed Shape and Seed Color). This led to Mendel&#8217;s third law. Understanding the 16-square Punnett grid is a vital skill for any <strong>principles of inheritance and variation pdf<\/strong> worksheet.<\/p>\n\n        <div class=\"formula-orange\">\n            <span class=\"formula-orange-label\">DIHYBRID PHENOTYPIC RATIO<\/span>\n            <div class=\"formula-orange-content\">9 : 3 : 3 : 1<\/div>\n            <p style=\"font-size: 0.85rem; margin-top: 5px;\">(9 Round Yellow : 3 Round Green : 3 Wrinkled Yellow : 1 Wrinkled Green)<\/p>\n        <\/div>\n\n        <h3>Law of Independent Assortment<\/h3>\n        <p>When two pairs of traits are combined in a hybrid, segregation of one pair of characters is independent of the other pair. This law holds true as long as the genes are located on different chromosomes or are far apart on the same chromosome.<\/p>\n\n        <h2><div class=\"badge\">05<\/div><span>Non-Mendelian Inheritance: Deviations<\/span><\/h2>\n        <p>Post-Mendelian research revealed that inheritance is often more complex than simple dominance. These deviations are frequent NEET targets in <strong>principles of inheritance and variation pdf<\/strong> assessments.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">INCOMPLETE DOMINANCE<\/span>\n                F<sub>1<\/sub> phenotype is intermediate between parents (e.g., Snapdragon red x white = pink). Ratio: 1:2:1.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">CO-DOMINANCE<\/span>\n                Both alleles express themselves simultaneously (e.g., ABO Blood groups). I<sup>A<\/sup> and I<sup>B<\/sup> are co-dominant.\n            <\/div>\n        <\/div>\n\n        <ul>\n            <li><strong>Multiple Alleles:<\/strong> Presence of more than two alleles for a single gene in a population (e.g., Gene &#8216;I&#8217; has 3 alleles).<\/li>\n            <li><strong>Pleiotropy:<\/strong> A single gene influencing multiple phenotypic traits (e.g., Phenylketonuria).<\/li>\n            <li><strong>Polygenic Inheritance:<\/strong> Multiple genes controlling a single trait (e.g., Human skin color, height).<\/li>\n        <\/ul>\n\n        <h2><div class=\"badge\">06<\/div><span>Chromosomal Theory, Linkage, and Recombination<\/span><\/h2>\n        <p>Proposed by Sutton and Boveri, the <strong>Chromosomal Theory of Inheritance<\/strong> identifies chromosomes as the carriers of genetic material. T.H. Morgan later provided experimental evidence using <em>Drosophila melanogaster<\/em>.<\/p>\n\n        <div class=\"callout warning\">\n            <div class=\"callout-pill\">WARN<\/div>\n            <strong>Linkage:<\/strong> Physical association of genes on a chromosome. Linked genes do not show independent assortment. High linkage = Low recombination frequency.\n        <\/div>\n\n        <div class=\"formula-dark\">\n            <span class=\"formula-dark-label\">RECOMBINATION CONCEPT<\/span>\n            <div class=\"formula-dark-content\">Recombination Frequency = (No. of Recombinants \/ Total Progeny) x 100<\/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\">07<\/div><span>Sex Determination: Principles of Inheritance and Variation PDF Summary<\/span><\/h2>\n        <p>Sex determination mechanisms vary across the animal kingdom. In humans, the presence of the Y-chromosome dictates the male sex. In birds, however, the female is the heterogametic sex.<\/p>\n\n        <div class=\"table-container\">\n            <table>\n                <thead>\n                    <tr>\n                        <th>Mechanism Type<\/th>\n                        <th>Heterogametic Sex<\/th>\n                        <th>Example Organism<\/th>\n                    <\/tr>\n                <\/thead>\n                <tbody>\n                    <tr>\n                        <td>XX &minus; XY<\/td>\n                        <td>Male (XY)<\/td>\n                        <td>Humans, Drosophila<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>XX &minus; XO<\/td>\n                        <td>Male (XO)<\/td>\n                        <td>Grasshopper<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>ZZ &minus; ZW<\/td>\n                        <td>Female (ZW)<\/td>\n                        <td>Birds, Butterflies<\/td>\n                    <\/tr>\n                    <tr>\n                        <td>Haplodiploidy<\/td>\n                        <td>Male (Haploid)<\/td>\n                        <td>Honeybees<\/td>\n                    <\/tr>\n                <\/tbody>\n            <\/table>\n        <\/div>\n\n        <h2><div class=\"badge\">08<\/div><span>Genetic Disorders: Mendelian and Chromosomal<\/span><\/h2>\n        <p>Disorders are broadly categorized based on their inheritance patterns. This section of the <strong>principles of inheritance and variation pdf<\/strong> is highly tested for pedigree analysis.<\/p>\n\n        <h3>1. Mendelian Disorders<\/h3>\n        <p>Determined by alteration or mutation in a single gene. They follow Mendelian inheritance patterns.<\/p>\n        <ul>\n            <li><strong>Haemophilia:<\/strong> Sex-linked recessive; blood fails to clot.<\/li>\n            <li><strong>Sickle-cell Anaemia:<\/strong> Autosomal recessive; GAG changes to GUG at 6th position of &beta;-globin chain.<\/li>\n            <li><strong>Phenylketonuria (PKU):<\/strong> Autosomal recessive; metabolic error in enzyme phenylalanine hydroxylase.<\/li>\n        <\/ul>\n\n        <h3>2. Chromosomal Disorders<\/h3>\n        <p>Caused by absence, excess, or abnormal arrangement of one or more chromosomes. Often due to non-disjunction during meiosis.<\/p>\n\n        <div class=\"card-grid\">\n            <div class=\"card\">\n                <span class=\"card-title\">DOWN&#8217;S SYNDROME<\/span>\n                Trisomy of chromosome 21. Features: Short stature, furrowed tongue, mental retardation.\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">KLINEFELTER&#8217;S<\/span>\n                Presence of an extra X-chromosome in males (44 + XXY). Sterile, show feminized features (Gynaecomastia).\n            <\/div>\n            <div class=\"card\">\n                <span class=\"card-title\">TURNER&#8217;S SYNDROME<\/span>\n                Absence of one X-chromosome in females (44 + XO). Sterile with rudimentary ovaries.\n            <\/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>Mendel:<\/strong> Selected 7 pairs of traits in garden peas.<\/li>\n                <li><strong>Segregation:<\/strong> Alleles separate during gamete formation (Universal Law).<\/li>\n                <li><strong>Test Cross:<\/strong> Crossing F<sub>1<\/sub> with recessive parent to find genotype.<\/li>\n                <li><strong>ABO Blood Group:<\/strong> Shows Multiple Allelism and Co-dominance.<\/li>\n                <li><strong>Morgan:<\/strong> Discovered Linkage in Drosophila.<\/li>\n                <li><strong>Henking:<\/strong> Discovered the X-body (X-chromosome).<\/li>\n                <li><strong>Sickle-cell:<\/strong> Point mutation; Glutamic acid replaced by Valine.<\/li>\n                <li><strong>Aneuploidy:<\/strong> Gain or loss of a chromosome (e.g., 2n + 1).<\/li>\n                <li><strong>Polyploidy:<\/strong> Increase in whole set of chromosomes (Common in plants).<\/li>\n                <li><strong>Pedigree Chart:<\/strong> Square = Male, Circle = Female, Colored = Affected.<\/li>\n            <\/ul>\n            <a href=\"#\" class=\"download-btn\" rel=\"nofollow noopener noreferrer\">\n                <span>Download Genetics PDF Summary<\/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>What is a Test Cross and what is its significance?<\/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\">A test cross involves crossing an organism with a dominant phenotype but unknown genotype (TT or Tt) with a homozygous recessive parent (tt). If the offspring are 100% tall, the unknown was TT. If they are 50% tall and 50% dwarf (1:1 ratio), the unknown was heterozygous (Tt). It is essential for determining genetic purity.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Explain the difference between Dominance and Co-dominance.<\/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 Dominance, only the dominant allele expresses itself in the heterozygote (e.g., Tt is Tall). In Co-dominance, both alleles express their traits simultaneously in the heterozygote (e.g., I<sup>A<\/sup>I<sup>B<\/sup> blood group has both A and B antigens).<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Why did Mendel choose the Pea plant for his experiments?<\/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\">Mendel chose <em>Pisum sativum<\/em> because: 1. It has many distinct contrasting traits. 2. It has a short life span. 3. It normally self-pollinates but can be easily cross-pollinated. 4. It produces a large number of offspring, providing a large data sample for statistical accuracy.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What is the molecular basis of Sickle-cell Anaemia?<\/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 is caused by a point mutation in the &beta;-globin gene. The triplet GAG (coding for Glutamic Acid) is mutated to GUG (coding for Valine) at the sixth position. This causes the hemoglobin to polymerize under low oxygen tension, changing the RBC shape from biconcave to sickle-shaped.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>Explain the concept of Linkage.<\/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\">Linkage is the physical association of genes on the same chromosome. Genes that are located very close together tend to be inherited as a unit and do not show independent assortment. The strength of linkage is inversely proportional to the distance between genes.<\/div>\n            <\/details>\n            <details>\n                <summary>\n                    <span>What is Trisomy and provide an example?<\/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\">Trisomy is a chromosomal abnormality where an organism has three copies of a particular chromosome instead of the normal two (2n + 1). Down&#8217;s Syndrome is an example of Trisomy 21, resulting in significant developmental and physical delays.<\/div>\n            <\/details>\n        <\/div>\n\n        <div class=\"cta-section\">\n            <h2>Inherit Excellence with KSquare career institute<\/h2>\n            <p>Mastering the <strong>principles of inheritance and variation pdf<\/strong> content is your gateway to a perfect score in NEET Biology. Join KSquare Institute&#8217;s Mission 180 Rankers Batch for expert-led lectures, interactive Punnett workshops, and high-yield study resources 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 Genetics and Inheritance Mastering the fundamental concepts of this chapter is essential for any medical aspirant. This comprehensive principles of inheritance and variation pdf guide provides a high-yield analysis of how traits are passed from parents to offspring and the mechanisms that drive biological diversity. Genetics is the branch of biology that [&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":[496,474,497,495,494,493,498,492,499,491],"class_list":["post-4105","post","type-post","status-publish","format-standard","hentry","category-free-study-material","tag-biology-class-12-chapter-5-notes","tag-class-12-biology-notes","tag-genetics-revision-notes","tag-heredity-and-variation-pdf","tag-inheritance-and-variation-notes","tag-mendelian-genetics-class-12","tag-ncert-biology-inheritance-chapter","tag-neet-biology-genetics","tag-neet-genetics-notes","tag-principles-of-inheritance-and-variation-pdf"],"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\/4105","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=4105"}],"version-history":[{"count":2,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4105\/revisions"}],"predecessor-version":[{"id":4275,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/posts\/4105\/revisions\/4275"}],"wp:attachment":[{"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/media?parent=4105"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/categories?post=4105"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ksquareinstitute.in\/blog\/wp-json\/wp\/v2\/tags?post=4105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}