A-Level Biology Revision
In-depth A-Level Biology revision covering every major topic. Detailed explanations, worked examples and exam strategy.
Biological Molecules
Carbohydrates, lipids, proteins and nucleic acids — structure and function.
Read guide →Cell Membrane
Fluid mosaic model, transport across membranes, osmosis and active transport.
Read guide →Enzymes in Detail
Induced fit model, inhibitors, cofactors, and enzyme kinetics.
Read guide →DNA Replication
Semi-conservative replication, Meselson-Stahl experiment, and proof.
Read guide →Protein Synthesis
Transcription, translation, mRNA, tRNA and ribosomes.
Read guide →The Cell Cycle
Interphase, mitosis, cancer and control of the cell cycle.
Read guide →Transport in Plants
Xylem, phloem, transpiration, translocation and the cohesion-tension theory.
Read guide →Circulatory System
Heart structure, cardiac cycle, blood vessels and haemoglobin.
Read guide →Gas Exchange
Lungs, alveoli, fish gills, insect tracheae and surface area to volume ratio.
Read guide →Immune System
Innate and adaptive immunity, T cells, B cells, antibodies and vaccination.
Read guide →Communicable Diseases
Pathogens, transmission, plant and animal diseases, and defence mechanisms.
Read guide →Photosynthesis
Light-dependent and light-independent reactions, Calvin cycle, limiting factors.
Read guide →Respiration
Glycolysis, Krebs cycle, oxidative phosphorylation and anaerobic pathways.
Read guide →Energy Transfer
Trophic levels, productivity, farming practices and energy budgets.
Read guide →Populations
Population growth, carrying capacity, predator-prey cycles and sampling.
Read guide →Succession
Primary and secondary succession, climax communities and conservation.
Read guide →Gene Expression
Epigenetics, transcription factors, RNA interference and body plans.
Read guide →Genetic Engineering
Restriction enzymes, vectors, PCR, gene therapy and GM organisms.
Read guide →Cloning
Natural and artificial cloning, therapeutic cloning, and ethical considerations.
Read guide →Speciation
Allopatric and sympatric speciation, reproductive isolation and gene pools.
Read guide →Taxonomy
Classification systems, phylogenetics, molecular evidence and three domains.
Read guide →Biodiversity & Conservation
Measuring biodiversity, threats, and in-situ vs ex-situ conservation.
Read guide →Kidney Function
Ultrafiltration, selective reabsorption, osmoregulation and dialysis.
Read guide →Muscle Contraction
Sliding filament theory, actin, myosin, sarcomeres and neuromuscular junctions.
Read guide →Synapse Transmission
Synaptic vesicles, neurotransmitters, summation and drug effects.
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