🧬 Class 12 Biology — Last 2 Days Crash Revision 2026
RBSE 20 Feb / CBSE 27 Feb Master Plan
Reproduction + Genetics + Ecology + Biotechnology — सम्पूर्ण Revision
⏰ RBSE: 2 दिन बाकी — 20 Feb!
📢 RBSE Class 12 Biology (Code 33): 20 फरवरी 2026 (शुक्रवार), 8:30 - 11:45 AM — सिर्फ 2 दिन!
📢 CBSE Class 12 Biology (044): 27 फरवरी 2026 — 9 दिन!
🎯 Biology = Diagram + NCERT Lines! कोई derivation नहीं, कोई numericals नहीं। NCERT रटो = marks पक्के!
📢 CBSE Class 12 Biology (044): 27 फरवरी 2026 — 9 दिन!
🎯 Biology = Diagram + NCERT Lines! कोई derivation नहीं, कोई numericals नहीं। NCERT रटो = marks पक्के!
📊 Unit-wise Weightage — 70 marks (Theory)
14
🌸 Reproduction
Ch.1-4
Ch.1-4
20
🧬 Genetics & Evolution
Ch.5-7 ⭐ HIGHEST
Ch.5-7 ⭐ HIGHEST
14
🏥 Human Welfare
Ch.8-10
Ch.8-10
8
🔬 Biotechnology
Ch.11-12
Ch.11-12
14
🌿 Ecology
Ch.13-16 — सबसे EASY!
Ch.13-16 — सबसे EASY!
🎯 Strategy: Genetics (20) + Ecology (14) + Reproduction diagrams (14) = 48/70 marks — ये 3 units master करो!
🌸 Unit 6: REPRODUCTION — 14 marks
Ch.1: Reproduction in Organisms (जीवों में जनन)
Key Points: Asexual reproduction types — Binary Fission, Budding, Fragmentation, Sporulation, Vegetative Propagation। Sexual reproduction — Meiosis, Gamete formation, Fertilisation। Parthenogenesis (बिना निषेचन)।
📌 Must Know: Asexual = genetically identical (clones), Sexual = genetic variation। Meiocytes → Gametes (n)।
Ch.2: Sexual Reproduction in Flowering Plants ⭐ DIAGRAM HEAVY
Key Points: T.S. of Anther (microsporogenesis), Structure of Ovule (megasporogenesis), Pollination types (self/cross), Double Fertilisation (syngamy + triple fusion), Endosperm development, Embryo development, Apomixis, Polyembryony।
📖 Ch.2 Notes →
⭐ MUST-DRAW DIAGRAMS:
1. T.S. of Anther showing microsporangia
2. Structure of Anatropous Ovule
3. 7-celled 8-nucleate Embryo Sac
4. Stages of Embryo Development (Dicot)
5. Double Fertilisation diagram
1. T.S. of Anther showing microsporangia
2. Structure of Anatropous Ovule
3. 7-celled 8-nucleate Embryo Sac
4. Stages of Embryo Development (Dicot)
5. Double Fertilisation diagram
📷 Anther T.S. + Ovule + Embryo Sac — ये 3 diagrams ज़रूर draw करो!
Ch.3: Human Reproduction ⭐ MOST IMPORTANT
Key Points: Male Reproductive System (Testes, Seminiferous tubules, Sertoli cells, Leydig cells), Female Reproductive System (Ovary, Fallopian tube, Uterus), Spermatogenesis, Oogenesis, Menstrual Cycle (28 days), Fertilisation, Implantation, Placenta, Parturition, Lactation।
📖 Ch.3 Notes →
⭐ MUST-DRAW:
1. Human Male Reproductive System
2. Human Female Reproductive System
3. Sectional view of Seminiferous Tubule
4. Spermatogenesis & Oogenesis flowchart
5. Menstrual Cycle graph (LH, FSH, Estrogen, Progesterone)
1. Human Male Reproductive System
2. Human Female Reproductive System
3. Sectional view of Seminiferous Tubule
4. Spermatogenesis & Oogenesis flowchart
5. Menstrual Cycle graph (LH, FSH, Estrogen, Progesterone)
📷 Male & Female Reproductive System + Menstrual Cycle Graph — हर साल पूछा जाता है!
Ch.4: Reproductive Health
Key Points: Family Planning methods — Natural (Rhythm, Withdrawal), Barrier (Condom, Diaphragm), IUDs (CuT, LNG-20), Hormonal (Pills, Implants), Surgical (Vasectomy, Tubectomy)। STDs (Gonorrhoea, Syphilis, HIV), Infertility (IVF, ZIFT, GIFT, ICSI), Amniocentesis (banned for sex determination)।
📌 Table बनाओ: Contraceptive methods — Name, Type, How it works
📖 Ch.4 Notes →🧬 Unit 7: GENETICS & EVOLUTION — 20 marks ⭐ HIGHEST
Ch.5: Molecular Basis of Inheritance ⭐⭐ MOST SCORING
Key Points: DNA Structure (Watson & Crick), DNA Replication (semi-conservative, Meselson-Stahl experiment), Transcription (DNA → mRNA), Translation (mRNA → Protein), Genetic Code properties, Lac Operon, Human Genome Project।
📖 Ch.5 Notes →
⭐ MUST-DRAW DIAGRAMS:
1. Structure of DNA double helix
2. Replication Fork (leading & lagging strand)
3. Transcription process
4. Translation (Initiation, Elongation, Termination)
5. Lac Operon (switched ON & OFF)
6. Meselson-Stahl experiment (3 generations)
1. Structure of DNA double helix
2. Replication Fork (leading & lagging strand)
3. Transcription process
4. Translation (Initiation, Elongation, Termination)
5. Lac Operon (switched ON & OFF)
6. Meselson-Stahl experiment (3 generations)
📷 DNA Replication Fork + Lac Operon (ON/OFF) — 20 marks unit से guaranteed questions!
🔑 Genetic Code Properties (याद करो):
- Triplet: 3 bases = 1 codon = 1 amino acid
- Universal: Same in all organisms
- Degenerate: Multiple codons for same amino acid
- Non-overlapping & Comma-less
- AUG: Start codon (Methionine) | UAA, UAG, UGA: Stop codons
Ch.6: Principles of Inheritance & Variation ⭐
Key Points: Mendel's Laws (Dominance, Segregation, Independent Assortment), Monohybrid (3:1), Dihybrid (9:3:3:1), Incomplete Dominance (1:2:1), Co-dominance (Blood groups), Sex-linked Inheritance (Colour blindness, Haemophilia), Sex Determination (XX-XY), Chromosomal Disorders (Down's = Trisomy 21, Turner's = 45,X, Klinefelter's = 47,XXY)।
⭐ MUST-PRACTICE:
1. Monohybrid & Dihybrid cross checker board
2. Incomplete dominance (Snapdragon flower)
3. Blood group inheritance (ABO)
4. Pedigree Analysis (5 patterns)
5. Colour blindness cross (carrier mother × normal father)
1. Monohybrid & Dihybrid cross checker board
2. Incomplete dominance (Snapdragon flower)
3. Blood group inheritance (ABO)
4. Pedigree Analysis (5 patterns)
5. Colour blindness cross (carrier mother × normal father)
Ch.7: Evolution
Key Points: Origin of Life (Oparin-Haldane, Miller-Urey experiment), Evidence (Homologous/Analogous organs, Fossils), Darwin's Natural Selection, Hardy-Weinberg Principle (p² + 2pq + q² = 1), Types of Selection (Stabilising, Directional, Disruptive), Human Evolution timeline।
📌 Must Know: Adaptive Radiation (Darwin's Finches, Australian Marsupials), Homologous = divergent evolution, Analogous = convergent evolution
📖 Ch.7 Notes →🏥 Unit 8: BIOLOGY IN HUMAN WELFARE — 14 marks
Ch.8: Human Health & Disease
Key Points: Diseases — Typhoid (Salmonella), Pneumonia (Streptococcus), Malaria (Plasmodium — lifecycle!), Amoebiasis, Ascariasis, Elephantiasis, Ringworm। Immunity — Innate vs Acquired, Active vs Passive, Humoral vs Cell-mediated। AIDS (HIV lifecycle), Cancer (Benign vs Malignant), Drugs & Alcohol abuse।
📌 Must-Draw: Life cycle of Plasmodium (Malaria parasite), Structure of Antibody (Y-shaped)
Ch.9: Strategies for Enhancement in Food Production
Key Points: Plant Breeding steps, Green Revolution (Norman Borlaug), Biofortification (Vitamin A — Golden Rice, Iron — fortified wheat), Single Cell Protein (SCP — Spirulina), Tissue Culture (Micropropagation, Somatic Hybridisation/Pomato), Apiculture, Pisciculture, Animal Husbandry — MUST programme।
📌 Table: Biofortified crops — Crop, Nutrient, Example variety
Ch.10: Microbes in Human Welfare
Key Points: Microbes in Household (Curd — Lactobacillus, Bread — Yeast, Toddy), Industrial Products (Ethanol, Antibiotics — Penicillin by Fleming), Biogas Plant (Methanobacterium), Sewage Treatment (Primary → Secondary → Tertiary), Biocontrol Agents (Bt, Ladybird), Biofertilizers (Rhizobium, Azospirillum, Mycorrhiza, Cyanobacteria)।
⭐ MUST-DRAW: Biogas Plant diagram (labelled)
🔬 Unit 9: BIOTECHNOLOGY — 8 marks
Ch.11: Biotechnology: Principles & Processes
Key Points: Genetic Engineering tools — Restriction Enzymes (molecular scissors, EcoRI), Cloning Vectors (pBR322), Competent Host (E. coli + CaCl₂)। rDNA Technology steps — Isolation → Cutting → Joining (Ligase) → Transfer → Screening। PCR (Polymerase Chain Reaction — Denaturation, Annealing, Extension), Gel Electrophoresis, Bioreactors (Stirred-tank)।
📌 Must-Draw: Steps of rDNA technology flowchart, PCR steps diagram, pBR322 plasmid map
Ch.12: Biotechnology & its Applications
Key Points: Bt Cotton (cry genes — cry1Ac, cry2Ab), Golden Rice (Vitamin A), RNAi (RNA interference — Meloidogyne nematode), Gene Therapy (ADA deficiency), Transgenic Animals, ELISA (diagnostic), Biopiracy, Bioethics, GMO controversy।
📌 Must Know: Bt toxin mechanism (crystals → gut → pores → death), ADA deficiency = first gene therapy success
🌿 Unit 10: ECOLOGY — 14 marks (सबसे EASY!)
📌 Note (Rationalized Syllabus 2024-26): NCERT ने कुछ topics हटाए हैं — Population interactions में detailed examples, Decomposition details, कुछ Environmental case studies। लेकिन chapter names और core concepts same हैं। नीचे सिर्फ syllabus में शामिल topics दिए हैं।
Ch.13: Organisms & Populations
Key Points: Abiotic factors (Temperature, Water, Light, Soil), Responses — Regulate, Conform, Migrate, Suspend (Hibernation/Aestivation)। Population attributes (Birth rate, Death rate, Sex ratio, Age pyramid), Growth models — Exponential (J-curve: dN/dt = rN) vs Logistic (S-curve: dN/dt = rN(K-N)/K)। Inter-specific interactions — Mutualism, Competition, Parasitism, Predation, Commensalism, Amensalism।
📌 Must-Draw: Exponential vs Logistic growth curve, Age pyramids (Expanding, Stable, Declining)
Ch.14: Ecosystem ⭐
Key Points: Ecosystem structure (Biotic + Abiotic), Productivity (GPP, NPP: NPP = GPP - R), Energy Flow (10% Law — Lindeman), Food Chain (Grazing vs Detritus), Food Web, Ecological Pyramids (Number, Biomass, Energy — always upright!), Nutrient Cycling (Carbon, Phosphorus), Ecological Succession (Primary → Secondary)।
⭐ MUST-DRAW:
1. Energy flow diagram (10% law)
2. Ecological Pyramids (Number — inverted for tree ecosystem, Biomass — inverted for aquatic, Energy — always upright)
3. Carbon Cycle
4. Phosphorus Cycle
5. Ecological Succession stages
1. Energy flow diagram (10% law)
2. Ecological Pyramids (Number — inverted for tree ecosystem, Biomass — inverted for aquatic, Energy — always upright)
3. Carbon Cycle
4. Phosphorus Cycle
5. Ecological Succession stages
📷 Ecological Pyramids + Carbon Cycle + Growth Curves — Ecology = सबसे easy 14 marks!
Ch.15: Biodiversity & Conservation
Key Points: 3 Levels (Genetic, Species, Ecological), Biodiversity patterns (Latitudinal gradient, Species-Area: log S = log C + Z log A), Causes of loss (HIPPO: Habitat loss, Invasive species, Pollution, Population, Over-exploitation), Conservation — In-situ (National Parks, Sanctuaries, Biosphere Reserves, Hotspots), Ex-situ (Zoos, Seed banks, Botanical gardens)।
📌 Must Know: India = Mega-diversity nation, 34 Biodiversity Hotspots worldwide (India: Western Ghats, Himalayas, Indo-Burma, Sundaland), Alexander von Humboldt — Species-Area relationship
Ch.16: Environmental Issues
Key Points: Air Pollution (SPM, SO₂, CO), Water Pollution (BOD — high = more polluted), Ozone Depletion (CFCs, UV-B), Global Warming (Greenhouse effect), Eutrophication, Biomagnification, Solid Waste Management, Radioactive Waste, Deforestation & Reforestation, Chipko, Bishnoi movement।
📌 Must Know: BOD = Biochemical Oxygen Demand, Electrostatic Precipitator for particulate matter, Catalytic converter for CO/NO
📅 2-Day Crash Plan — RBSE 20 Feb
🔥 आज का टारगेट (18 Feb) — Reproduction + Genetics = 34 marks
Morning (3 hrs): Ch.2 Sexual Reproduction in Plants — Anther T.S., Ovule, Double Fertilisation diagrams। Ch.3 Human Reproduction — Male/Female system, Spermatogenesis, Oogenesis, Menstrual Cycle।
📖 Ch.2 Notes → | 📖 Ch.3 Notes →
📖 Ch.2 Notes → | 📖 Ch.3 Notes →
Afternoon (3 hrs): Ch.5 Molecular Basis — DNA Replication, Transcription, Translation, Lac Operon, Genetic Code। ⭐ सबसे scoring!
📖 Ch.5 Notes →
📖 Ch.5 Notes →
Evening (2 hrs): Ch.6 Inheritance — Mendelian crosses, Pedigree Analysis, Blood groups, Sex-linked। Ch.4 Reproductive Health — contraceptives table, STDs।
📖 Ch.4 Notes →
📖 Ch.4 Notes →
✅ Day 1 done = 34 marks covered!
🔥 कल का टारगेट (19 Feb — EXAM परसों!) — Ecology + Welfare + Biotech = 36 marks
Morning (3 hrs): Ch.13-16 Ecology — Growth curves, 10% Law, Ecological Pyramids, Biodiversity, Succession, Environmental Issues। ⭐ सबसे easy unit!
📖 One-Shot Revision →
📖 One-Shot Revision →
Afternoon (2 hrs): Ch.8 Health & Disease — Malaria lifecycle, Immunity types, AIDS, Cancer। Ch.10 Microbes — Biogas Plant, Sewage Treatment, Biofertilizers।
Evening (2 hrs): Ch.11-12 Biotechnology — rDNA steps, PCR, Bt Cotton, Gene Therapy, Golden Rice।
Night (1 hr): ⭐ DIAGRAM REVISION: सभी diagrams एक बार draw करो — Anther, Ovule, Embryo sac, Male/Female system, DNA Replication, Lac Operon, Biogas Plant, Ecological Pyramids।
📖 Diagram Atlas → | 📖 Important Diagrams PDF →
📖 Diagram Atlas → | 📖 Important Diagrams PDF →
10 PM: 😴 सो जाओ! कल Biology exam। Fresh mind ज़रूरी। Admit Card, Pen (Blue+Black), Pencil, Scale ready रखो।
✏️ Must-Draw Diagrams Checklist — 15-20 marks!
🌸 Reproduction:
- T.S. of Anther (4 microsporangia)
- Structure of Anatropous Ovule
- 7-celled, 8-nucleate Embryo Sac
- Stages of Dicot Embryo Development
- Human Male Reproductive System
- Human Female Reproductive System
- Spermatogenesis & Oogenesis
- Menstrual Cycle (hormone graph)
🧬 Genetics:
- DNA Double Helix Structure
- Replication Fork (Okazaki fragments)
- Transcription (DNA → mRNA)
- Translation (ribosome, tRNA, mRNA)
- Lac Operon (ON & OFF)
- Dihybrid Cross Checker Board
🌿 Ecology & Others:
- Ecological Pyramids (Number, Biomass, Energy)
- Carbon Cycle & Phosphorus Cycle
- Exponential vs Logistic Growth Curves
- Biogas Plant (labelled)
- Life Cycle of Plasmodium
- Antibody Structure (Y-shape)
📷 ये 20 diagrams practice करो = 15-20 marks guaranteed!
🎯 Exam Day Strategy — 20 Feb 2026
📋 Attempt Order: MCQs → Ecology (easy, quick) → Diagrams (Reproduction) → Genetics → Biotechnology → Human Welfare
✏️ Diagrams: Pencil से draw, Pen से label, Title + Arrows + Parts clearly लिखो
📝 Long Answers: Diagrams include करो = bonus marks even if answer incomplete
🧬 Genetics: Cross लिखो — Parents → Gametes → F1 → F2 → Ratio
📖 NCERT Lines: Definitions exactly NCERT जैसी लिखो — examiner यही चाहता है
⏱️ Time: MCQs (20 min) → Ecology (25 min) → Reproduction (30 min) → Genetics (35 min) → Biotech (20 min) → Human Welfare (20 min) → Review (10 min)
📚 सम्पूर्ण Study Material
📖 Chapter Notes
🌸 Ch.2 Sexual Reproduction in Flowering Plants
🌸 Ch.3 Human Reproduction
🌸 Ch.4 Reproductive Health
🧬 Ch.5 Molecular Basis of Inheritance
🧬 Ch.7 Evolution
📖 Unit 6 Reproduction — Complete Guide
📖 Unit 7 Genetics & Evolution — Complete Guide
📝 Tests & Practice
🎯 Important Questions & Revision
🎯 Important Questions 2026
🎯 RBSE Important Questions
🎯 Most Expected Questions
🎯 Most Repeated Questions
📖 NCERT Line-by-Line Key Points
📖 One-Shot Revision Notes
📖 One-Page Revision Charts
📊 Chapter-wise Weightage
🎯 Exam Day Strategy
📅 30-Days Revision Plan
✏️ Diagrams & PDF
❓ FAQ
Q: RBSE Biology कब है?
20 Feb 2026 (शुक्रवार), 8:30-11:45 AM। 2 दिन!
Q: CBSE Biology कब है?
27 Feb 2026 (शुक्रवार)।
Q: सबसे ज़्यादा marks कहाँ से?
Genetics (Ch.5-7) = 20 marks! अकेला सबसे बड़ा unit। Ecology = 14 (easiest)।
Q: Most important diagrams?
Anther T.S., Embryo Sac, Reproductive Systems, DNA Replication Fork, Lac Operon, Ecological Pyramids, Biogas Plant।
Q: Genetics कैसे तैयार करें?
Ch.5 = DNA Replication + Transcription + Lac Operon। Ch.6 = Mendelian crosses + Pedigree। Diagrams draw करो!
Q: 2 दिन plan?
Day 1: Reproduction + Genetics (34 marks)। Day 2: Ecology + Welfare + Biotech (36 marks)। Night: All diagrams revise।
Q: NCERT से बाहर आएगा?
नहीं! RBSE & CBSE दोनों strictly NCERT based। NCERT lines रटो।
Q: Pass marks strategy?
Ecology (14) + Reproduction diagrams (10) + Genetics definitions (6) = 30 marks minimum।
📢 Biology RBSE 20 Feb — दोस्तों को भेजो!
WhatsApp, Telegram पर Share करो ↓
No comments:
Post a Comment