Most important Biology chapters for NEET
These chapters come up the most in past NEET papers, heaviest first. Give them the most time.
- Molecular Basis of InheritanceHighest-weightage chapter in the entire NEET paper.
- Animal KingdomLargest Zoology chapter; heavy on non-chordate classification detail.
- Biotechnology: Principles and Processes
- BiomoleculesFoundation
- Principles of Inheritance and Variation
- Cell Cycle and Cell DivisionFoundation
- Structural Organisation in Animals
- Reproductive HealthFar higher yield than students expect for its size.
- Plant Kingdom
- Anatomy of Flowering Plants
- Biotechnology and its Applications
Class 11 Biology chapters
| # | Chapter | Weightage |
|---|---|---|
| 01 | The Living WorldBotanyFoundationLowest-yield chapter in Biology, but taxonomy vocabulary is assumed later. | Lower |
| 02 | Biological ClassificationBotanyFoundation | Medium |
| 03 | Plant KingdomBotany | Very high |
| 04 | Animal KingdomZoologyLargest Zoology chapter; heavy on non-chordate classification detail. | Very high |
| 05 | Morphology of Flowering PlantsBotanyFoundationTerminology here is assumed by the rest of botany. | High |
| 06 | Anatomy of Flowering PlantsBotany | Very high |
| 07 | Structural Organisation in AnimalsZoology | Very high |
| 08 | Cell: The Unit of LifeBotanyFoundation | High |
| 09 | BiomoleculesZoologyFoundation | Very high |
| 10 | Cell Cycle and Cell DivisionBotanyFoundation | Very high |
| 11 | Photosynthesis in Higher PlantsBotany | Medium |
| 12 | Respiration in PlantsBotany | Medium |
| 13 | Plant Growth and DevelopmentBotany | High |
| 14 | Breathing and Exchange of GasesZoology | Medium |
| 15 | Body Fluids and CirculationZoology | High |
| 16 | Excretory Products and their EliminationZoology | High |
| 17 | Locomotion and MovementZoology | High |
| 18 | Neural Control and CoordinationZoology | Lower |
| 19 | Chemical Coordination and IntegrationZoology | Medium |
Class 12 Biology chapters
| # | Chapter | Weightage |
|---|---|---|
| 20 | Sexual Reproduction in Flowering PlantsBotany | High |
| 21 | Human ReproductionZoology | High |
| 22 | Reproductive HealthZoologyFar higher yield than students expect for its size. | Very high |
| 23 | Principles of Inheritance and VariationBotany | Very high |
| 24 | Molecular Basis of InheritanceBotanyHighest-weightage chapter in the entire NEET paper. | Very high |
| 25 | EvolutionZoology | High |
| 26 | Human Health and DiseaseZoology | High |
| 27 | Microbes in Human WelfareBotanyAlmost pure recall — high marks per hour. | Medium |
| 28 | Biotechnology: Principles and ProcessesZoology | Very high |
| 29 | Biotechnology and its ApplicationsZoology | Very high |
| 30 | Organisms and PopulationsBotany | Medium |
| 31 | EcosystemBotany | Medium |
| 32 | Biodiversity and ConservationBotany | Medium |
Key topics in the heaviest chapters
Each one is a single study sitting. Work through them in order.
Animal Kingdom
- Basis of classification: symmetry, coelom, germ layers
- Porifera through Ctenophora: distinguishing features
- Platyhelminthes, Aschelminthes, Annelida
- Arthropoda and Mollusca: examples and features
- Echinodermata and Hemichordata
- Chordate classes and their defining characters
Principles of Inheritance and Variation
- Mendel’s laws and the monohybrid/dihybrid ratios
- Deviations: incomplete dominance, codominance, multiple alleles
- Polygenic inheritance and pleiotropy
- Linkage, recombination and gene mapping
- Sex determination and sex-linked inheritance
- Pedigree analysis
- Genetic disorders: Mendelian and chromosomal
Molecular Basis of Inheritance
- DNA structure and the numbers: 34 Å, 3.4 Å, 10 bp
- The experiments: Griffith, Avery, Hershey–Chase, Meselson–Stahl
- Replication: enzymes, leading and lagging strands
- Transcription in prokaryotes vs eukaryotes
- Genetic code and its properties
- Translation: initiation, elongation, termination
- lac operon regulation with and without lactose
How to use this list
- Foundations first. The Living World, Biological Classification, Morphology of Flowering Plants and Cell: The Unit of Life look small, but later chapters depend on them.
- Then the very high chapters. They earn the most marks per hour. Revise them more than once.
- Never drop a chapter just because its tier is lower. One question can be the difference in rank.
- Track it. Mark each chapter as started, done or due for revision, so you always know what is left.
How we rank chapters
We compared published analyses of NEET papers from 2020 to 2024, including one that counted more than 250 questions per subject. The sources agree on which chapters come up most, but not on exact percentages, so we show tiers instead of numbers that look more precise than they are.
Chapters marked estimate have thin data, so treat their tier as a rough guide. Chapters marked Foundation may carry fewer direct questions, but other chapters depend on them. Do not skip them.
The chapter list follows the current NMC syllabus. The official 2027 syllabus comes with the information bulletin on neet.nta.nic.in. We update this page when it changes.
Questions students ask
How many chapters are in NEET 2027 Biology?
NEET Biology has 32 chapters: 19 from Class 11 and 13 from Class 12. The full list is on this page.
Which NEET Biology chapters have the highest weightage?
The heaviest are Molecular Basis of Inheritance, Animal Kingdom, Biotechnology: Principles and Processes, Biomolecules and Principles of Inheritance and Variation. In all, 11 Biology chapters are in the very high tier for NEET. Give them the most time, but finish the foundation chapters first.
Which Biology chapters should I study first?
Start with the foundation chapters: The Living World, Biological Classification, Morphology of Flowering Plants, Cell: The Unit of Life and Biomolecules. Later chapters build on them, even when they carry fewer direct questions. Then spend most of your time on the very high and high weightage chapters.
Is this the official NEET 2027 Biology syllabus?
It follows the current NMC syllabus. The official 2027 syllabus is published with the information bulletin on neet.nta.nic.in, and we update this page when it changes.