Free Biology Notes for Students
Complete Biology Toolkit in One Place
Biology Notes Online provides free study notes, lecture videos and microscopic images covering microbiology, botany, zoology, biochemistry, genetics, cell biology and laboratory methods for A-level, AP, IB, BSc and MSc students.
All Biology Topics
Explore Every Branch of Biology – Dive Deep, Scroll Wide, Learn Fast
- Agricultural Microbiology 12 posts
- Bacteriology 99 posts
- Basic Microbiology 93 posts
- Biochemistry 102 posts
- Bioinformatics 25 posts
- Biotechnology 11 posts
- Cell Biology 127 posts
- Environmental Microbiology 105 posts
- Food Microbiology 55 posts
- Genetics 99 posts
- Immunology 102 posts
- Industrial microbiology 24 posts
- Medical Microbiology 46 posts
- Microscope 28 posts
- Molecular biology 85 posts
- Mycology 48 posts
- Parasitology 32 posts
- Phycology 25 posts
- Prions 2 posts
- Protozoa 15 posts
- Virology 64 posts
- Angiosperms 31 posts
- Archegoniate 12 posts
- Biodiversity 1 post
- Economic Botany 14 posts
- Ethnobotany 5 posts
- Horticultural 10 posts
- Natural Resource Management 3 posts
- Plant Anatomy and Embryology 20 posts
- Plant Breeding 16 posts
- Plant Ecology and Taxonomy 15 posts
- Plant Physiology and Metabolism 18 posts
- Animal Behaviour 1 post
- Basic Zoology 6 posts
- Biology of Insecta 15 posts
- Chordates 27 posts
- Developmental Biology 20 posts
- Endocrinology 17 posts
- Ethology 6 posts
- Evolutionary Biology 21 posts
- Fish and fisheries 25 posts
- Human Anatomy 16 posts
- Neuroscience 17 posts
- Non-chordates 20 posts
- Pest Management 4 posts
- Physiology 52 posts
- Protista 15 posts
- Reproductive Biology 5 posts
- Research Methodology 7 posts
- Vertebrata 13 posts
- Biochemical Test 88 posts
- Botany Practicals 2 posts
- Culture Media 78 posts
- Cytopathology 1 post
- Hematology 7 posts
- Immunology Practical 19 posts
- Instruments 150 posts
- Laboratory Techniques 5 posts
- Laboratory Tests 14 posts
- Microbiology Techniques 26 posts
- Protocols 18 posts
- Staining 43 posts
- Under Microscope 25 posts
- Differences 170 notes
- Research Methodology 7 notes
- Syllabus 12 notes
- Bacteriology 99 posts
- Mycology 48 posts
- Parasitology 32 posts
- Phycology 25 posts
- Prions 2 posts
- Protozoa 15 posts
- Virology 64 posts
Latest Notes
Factors Affecting Bacterial Growth – Physical and Nutritional Requirements
Factors affecting bacterial growth include temperature, pH, oxygen, water availability, osmotic pressure, nutrients, and essential growth factors.
Cysticercosis: Causes, Symptoms, Diagnosis and Treatment
Cysticercosis is a tissue infection caused by Taenia solium larvae. Review transmission, symptoms, diagnosis, treatment, prevention and neurocysticercosis.
Aerobic vs Anaerobic Respiration – Key Differences
Aerobic respiration refers to a series of metabolic reactions that occur in the presence oxygen in a cell. It is used to convert chemical…
Amphibians vs Reptiles – Key Differences, Similarities & Examples
Amphibians belong to a class of vertebrates with cold blood that is adept at exploitation of terrestrial and aquatic habitats.
Asexual vs Sexual Reproduction – Key Differences
Asexual reproduction is the process of reproduction that does not involve gamestasy, and does not require the exchange of genetic information which results in…
Bacteria vs Virus – Key Differences & Similarities
The main difference between bacteria and viruses is based on their cellular structure and the way by which they multiply. Bacteria are unicellular organisms,…
Basidiomycetes vs Deuteromycetes – Key Differences, Similarities & Examples
Basidiomycetes and Deuteromycetes differ mainly in their reproductive structures, sexual stage, and taxonomic position. Basidiomycetes (Basidiomycota) are recognized fungi in which sexual spores called…
Integral Protein – Definition, Structure, Types, Functions & Examples
Integral protein explained: definition, membrane structure, monotopic, bitopic and polytopic types, functions, examples, and key comparisons.
Three-Domain System (Carl Woese’s Classification): Basis and Domains
Three-domain system (Carl Woese’s Classification) explained through its rRNA basis, three domains, key differences, and relationship to kingdom systems.
CRISPR-Cas9: Definition, Classification, Structure, Mechanism, Applications, and Limitations
CRISPR-Cas9 explained: meaning, components, mechanism, applications, limitations, history, ethics, and current uses in genome editing and medicine.
Discover the Microscopic World
Share and explore stunning microscopic images of microorganisms in our growing community.









