Biology Important Concepts, Formulae & Laws (CBSE, IGCSE, IB, JEE, NEET)

Quick Revision for School Boards (CBSE/ICSE/IGCSE/IB), NEET, JEE & Olympiads – By Hodu Academy
Your shortcut to Biology mastery! Here’s your all-in-one list for crucial Biology concepts, definitions, laws, diagrams and key terms – handpicked by Hodu Academy’s Biology team.
Perfect for last-minute revision, board exams (CBSE/ICSE/IGCSE/IB), NEET/JEE aspirants, and Olympiad toppers. Every topic is mapped for fast learning and exam scoring.

Bookmark this page as your Biology cheat-sheet—latest for 2025, and 100% relevant for IGCSE, IB & other international boards!
This page covers:
  • 350+ Key Biology concepts, definitions, diagrams & processes (IGCSE & IB compatible)
  • Important cycles, physiological laws, and quick facts
  • Short explanations, differences & diagrams (cell, tissues, reproduction, more)
  • SI units & constants in Biology
  • Rapid revision for boards, NEET, Olympiads & interviews

Why Use This Biology Cheat Sheet?

Biology connects us to the living world, health, and nature. It is crucial for NEET, JEE (Bio), Olympiads, CBSE, ICSE, IGCSE, IB and more. But Biology involves hundreds of terms, definitions, cycles, diagrams, and tricky differences.

This page helps you:
  • Revise hundreds of definitions, diagrams, cycles and differences in minutes
  • Look up every important law, classification, process or definition instantly
  • Find biological terms, cycles, or diagrams that are always asked in exams
  • Be ready for IGCSE, IB & NEET Biology questions

Tip: Boost recall with Biology MCQ quizzes and diagram practice!

Complete Biology Important Concepts, Definitions & Laws List

300+ must-know Biology topics for Boards & Competitive Exams (including IGCSE & IB)
Categories covered: Cell Biology, Genetics, Plant & Animal Physiology, Classification, Ecology, Environment, Health & Disease, and more!
Mapped to: CBSE, ICSE, IGCSE, IB Diploma, NEET, JEE & Olympiads
Conservation of Forest and Wildlife Difference between Endosmosis and Exosmosis Difference between Afforestation and Deforestation Difference between Algae and Fungi Difference between Cereals and Pulses
Difference Between Fragmentation and Regeneration Difference Between Neurosis and Psychosis Difference Between Nucleotide and Nucleoside Difference Between Sea and Ocean Difference Between Turtles and Tortoises
Difference Between Wildlife Sanctuary and National Park Modes of Plant Reproduction Ecological Pyramid and Its Types Double Fertilization in Angiosperms Ecosystem
Enzymes Fertilisation in Plants Five Kingdoms Classification Flower Ganongs Potometer
Health and Hygiene Herbivores and Carnivores Heterotrophic Nutrition Human Digestive System Vertebrates and Invertebrates
Morphology of Leaves Modifications of Root Phylum Aschelminthes Diffusion Osmosis
Prokaryotic Cells Reproduction Flora And Fauna Overview of Food Chain Difference Between Rabi And Kharif Crops
Vegetative Propagation Transpiration Soil Profile Types of Pollution Human Excretory System
Sense Organs Rainwater Harvesting Prokaryotic And Eukaryotic Cells Living And Non Living Things The Nucleus
Irrigation Endoplasmic Reticulum Difference Between Data And Information Mitochondria Nitrogen Cycle
Diagram of Animal Cell Meristematic Tissue Law of Segregation Law of Dominance Eukaryotic Cells Food Sources Animal Plant Products
Photosynthesis Respiration Ozone Layer Depletion Kingdom Fungi Aerobic Anaerobic Respiration
Cell Organelles Peristalsis Bacteria Oogenesis Leaves Morphology Types Modification
Mitosis and Meiosis Dna Structure How Do Organisms Reproduce Diagram of Stomata Monohybrid Cross Inheritance One Gene
Mechanism of Breathing Soil Erosion Plasmolysis Urine Formation Osmoregulation Porifera
Flagella Amoeba Aerobic Respiration Pteridophyta Arteries And Veins Difference
Reflex Action Stomata Cell Wall Diagram of Neuron A Guide To Composition And Function Of Lymph
Difference Between Ligaments And Tendons Insectivorous Plants Nutrition Modes Living Organisms Mendel Laws Of Inheritance Nutrition In Amoeba
Calorific Value Air Pollution Control Fertilization In Plants Life Processes Binary Fission
Omnivores Saprophytes Asexual Reproduction Deficiency Diseases Light Reaction Vs Dark Reaction
Global Warming Wildlife Sanctuary Viviparous Oviparous Embryo Development Glycolysis Food Preservation Methods Food Poisoning
Crops Biofertilizers Biodiversity Conservation Difference Between Endocrine And Exocrine Glands Greenhouse Effect Gases
Diagram Of Digestive System Crop Production And Management Types Of Pollination Introduction and Characteristics of Living Beings Meristematic Cells
Taxonomical Aids _Flora, Manual, Monograph And Catalogues Types of leaves structure of skeletal muscle spirometry human respiratory system
herbarium dinoflagellates general characters and structure of leaf halophiles and their features Exchange of Gases
Simple Permanent tissue Morphology of root and its types Complex permanent tissues Regions of Root History of classification and its need
Breathing And Exchange Of Gases Transport of Gases Regulation of Respiration Disorders of Respiratory System Interaction of Haemoglobin with Other Gases
Amniocentesis Anatomy of flowering plants ASSISTED REPRODUCTIVE TECHNOLOGIES (ARTs) Meristematic Cells Phloems
Population explosion Reproductive Health RCH (Reproductive and Child Health Care) Medical termination of Pregnancy (MTP) Plant kingdom
Biological Systems of Classification & Branches of Taxonomy Pteridophytes Gymnosperms Angiosperms Life cycle Patterns
Anatomy of Roots Contraceptives Anatomy of stem Algae Bryophytes
Tissues and its types STDs (Sexually Transmitted Diseases) Cell - The Basic Unit of Life & its Historical background Cell theory and its modification An Overview of Cell
Secondary growth in dicot stem Tissue system and types Prokaryotic (Bacterial) cell Ribosomes Eukaryotic cell
Cell: The basic unit of life Cytoskeleton Centrosome and Centriole Cilia and flagella Nucleus
Chromosomes Evolution Movement and Locomotion Human Reproduction Absorption and Translocation of Solutes
Soil as a reservoir of Essential Elements LOCOMOTION AND MOVEMENT Mechanism of Muscle Contraction Morphology in Flowering Plants Contractile proteins
Muscular System Thyroid Puberty Hormones Origin of Universe
Hypothalamus Cell wall Mitochondria Special Chromosomes Microbodies
Introduction, Hydroponics and the study of mineral requirements of the plants Criteria of essentiality and Categorisation of Essential elements Deficiency symptoms of essential elements and toxicity The Stem The Root
Cytoplasm and cell membrane Mineral Nutrition Male Reproductive System Phylum Ctenophora Role of Macronutrients
Role of Micronutrients Phylum - Coelenterata / Cnidaria Reptilia Aves Mammalia
Anatomy of the leaf Animal kingdom Phylum Annelida Phylum Mollusca Phylum Echinodermata
Vertebrata Chordates Disorders of circulatory system Abiotic Factors Male Reproductive System
Kingdom Animalia Responses to Abiotic Factors Female Reproductive System Mammary Glands Pregnancy and Embryonic Development
Cell Cancer Disorders of the Digestive System Infertility Morphology of Cockroach
Blood and Plasma Alternation of Generations and Classification Predation Phaeophyceae and Rhodophyceae Phylum Coelenterata
Phylum Porifera Phylum Platyhelminthes Chromosomal Disorders Competition Taxonomic Aids
Alternation of generation in Pteridophytes Disorders of muscular and skeletal system General Characteristics of Living Digestive Glands Stomach
Testis Buccal cavity Seed Common Diseases in Humans Permanent Tissue
Permanent Tissues Xylem Pteridophytes Characteristics Parasitism and Commensalism Water Pollution and Its Control Differentiation, Dedifferentiation and Redifferentiation
Organism and its Environment Carbohydrates Greenhouse Effect Gases Amino Acids Dynamic State of Body Constituents
Photosynthesis Chloroplast Features of Living Beings Blood Group Lipids Kingdom Protista
dense connective tissue connective tissue cartilage connective tissue blood plant cell viruses
the stem Connective Tissue Bone Viroids Prions Lichens Animal cell Prokaryotic Cell
Taxonomic Aids Herbarium and Museum Sphygmomanometer and ECG Population Attributes Noise pollution  

Biology Must-Know Laws, Principles & Cycles

Important Laws, Cycles & Principles:
  • Mendel’s Laws of Inheritance (Dominance, Segregation, Independent Assortment)
  • Cell Theory, Modern Cell Theory
  • Lamarckism, Darwin’s Theory of Evolution, Neo-Darwinism
  • Hardy-Weinberg Principle, Biological Classification
  • Photosynthesis, Respiration (Aerobic & Anaerobic), Nitrogen Cycle, Carbon Cycle, Water Cycle
  • Enzyme Action, Lock and Key Hypothesis
  • Ecological Pyramid, Food Chain & Food Web, Biogeochemical Cycles
  • Principles of Homeostasis, Feedback Mechanisms
  • Central Dogma of Molecular Biology

SI Units & Constants:
  • Cell diameter (μm), Life span (years, days, hours), Chromosome number No
  • Enzyme concentration (μmol/L), Population density (individuals/km²)
  • Blood pressure (mm Hg), Body temperature (°C), Pulse rate (bpm)
  • pH scale (unitless), Genetic frequency (%)

Tips to Score 90+ in Biology

  • Practice labelling diagrams, cycles and definitions (use this list for daily recall!)
  • Memorize key terms, physiological laws, and differences (difference between…)
  • Review all classifications, cycles, plant/animal physiology topics and genetic laws
  • Use Hodu Academy’s Biology MCQs and diagram practice sheets for rapid revision
For PDF downloads, practice sheets, or doubts, Contact Hodu Academy now!
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Last modified: Friday, 11 July 2025, 7:47 PM