Edexcel · A-Level
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Start with the first Biology lesson.
Why Animals Need a Circulatory System
1Why Animals Need a Circulatory SystemRead next2The Role of Diffusion in TransportRead next3Water as a Solvent in TransportRead next4Dipole Nature of WaterRead next5Structure and Function of CapillariesRead next6Structure and Function of ArteriesRead next7Structure and Function of VeinsRead next8The Cardiac Cycle: Atrial SystoleRead next9The Cardiac Cycle: Ventricular SystoleRead next10The Cardiac Cycle: Cardiac DiastoleRead next11Heart Structure and Function OverviewRead next12Investigating Heart Structure PracticallyRead next13The Process of AtherosclerosisRead next14Stages of Atherosclerosis DevelopmentRead next15The Blood-Clotting ProcessRead next16Thromboplastin and Prothrombin ConversionRead next17Fibrinogen to Fibrin in ClottingRead next18Blood Clots and Cardiovascular DiseaseRead next19Genetic Risk Factors for Cardiovascular DiseaseRead next20Lifestyle Risk Factors for Cardiovascular DiseaseRead next21Quantitative Data on Health RisksRead next22Correlation vs. Causation in Health StudiesRead next23Conflicting Evidence in Health DataRead next24Evaluating Health Risk Study DesignsRead next25Sample Selection and Sample Size in StudiesRead next26Perceptions vs. Actual Risks in HealthRead next27Energy Budgets and Diet AnalysisRead next28Consequences of Energy ImbalanceRead next29Monosaccharides: Structure and RoleRead next30Disaccharides: Structure and RoleRead next31Polysaccharides: Glycogen and StarchRead next32Condensation Reactions and Glycosidic BondsRead next33Hydrolysis of CarbohydratesRead next34Triglyceride Synthesis and Ester BondsRead next35Differences Between Saturated and Unsaturated LipidsRead next36Health Significance of Blood Cholesterol LevelsRead next37High-Density vs. Low-Density LipoproteinsRead next38Causal Relationship Between Cholesterol and CVDRead next39Obesity Indicators: BMI and Waist-to-Hip RatioRead next40Using Diet and Exercise to Reduce CVD RiskRead next41Smoking and Coronary Heart Disease RiskRead next42Core Practical: Effect of Caffeine on Daphnia Heart RateRead next43Ethical Issues in Using Invertebrates in ResearchRead next44Core Practical: Vitamin C Content in Food and DrinkRead next45Benefits of Antihypertensives for CVDRead next46Risks of Antihypertensives for CVDRead next47Statins: Benefits and RisksRead next48Anticoagulants and Platelet Inhibitors in CVD TreatmentRead next
Properties of Gas Exchange Surfaces
1Properties of Gas Exchange SurfacesRead next2Fick's Law of DiffusionRead next3Adaptations of Mammalian LungsRead next4Structure and Properties of Cell MembranesRead next5The Fluid Mosaic ModelRead next6Core Practical: Membrane PermeabilityRead next7Osmosis and Free Water MoleculesRead next8Passive Transport MechanismsRead next9Active Transport and ATP RoleRead next10Endocytosis and ExocytosisRead next11Carrier and Channel Proteins in TransportRead next12Structure of MononucleotidesRead next13DNA and RNA StructuresRead next14Complementary Base Pairing in DNARead next15The DNA Double HelixRead next16Transcription in Protein SynthesisRead next17Translation and Role of tRNARead next18Start and Stop Codons in Protein SynthesisRead next19The Triplet Code and DegeneracyRead next20Genes and Polypeptide ChainsRead next21Structure of Amino AcidsRead next22Formation of Peptide BondsRead next23Protein Primary Structure and 3D ShapeRead next24Globular vs Fibrous ProteinsRead next25Haemoglobin and Collagen StructuresRead next26Enzyme Specificity and 3D StructureRead next27Enzymes as Biological CatalystsRead next28Intracellular vs Extracellular EnzymesRead next29Core Practical: Enzyme Reaction RatesRead next30DNA Replication ProcessRead next31Role of DNA Polymerase in ReplicationRead next32Meselson and Stahl's ExperimentRead next33DNA Replication Errors and MutationsRead next34Gene Mutations in Cystic FibrosisRead next35Key Genetic Terms and DefinitionsRead next36Monohybrid Inheritance PatternsRead next37Interpreting Genetic Pedigree DiagramsRead next38Cystic Fibrosis and System ImpairmentsRead next39Uses of Genetic ScreeningRead next40Pre-implantation Genetic Diagnosis (PGD)Read next41Prenatal Testing MethodsRead next42Amniocentesis vs Chorionic Villus SamplingRead next43Implications of Prenatal ScreeningRead next44Social Issues in Genetic ScreeningRead next45Ethical Issues in Genetic ScreeningRead next
The Structure of Eukaryotic Cells
1The Structure of Eukaryotic CellsRead next2Functions of Eukaryotic OrganellesRead next3The Structure of Prokaryotic CellsRead next4Comparison of Eukaryotic and Prokaryotic CellsRead next5Recognising Organelles in Electron MicrographsRead next6Specialisation of Mammalian GametesRead next7The Process of Fertilisation in MammalsRead next8Gene Loci and Chromosome LinkageRead next9Sex Linkage of GenesRead next10Genetic Variation Through MeiosisRead next11Independent Assortment and Crossing OverRead next12Role of Mitosis in Growth and ReproductionRead next13The Cell Cycle and Its PhasesRead next14Preparing and Staining Root Tip SquashesRead next15Stem Cells: Definition and TypesRead next16Pluripotency vs Totipotency in Stem CellsRead next17Stem Cells in Medical TherapiesRead next18Differential Gene Expression in Cell SpecialisationRead next19The Lac Operon and Gene RegulationRead next20Organisation of Cells into Tissues and SystemsRead next21Genotype and Environment Interaction on PhenotypeRead next22Epigenetic Changes: DNA MethylationRead next23Epigenetic Changes: Histone ModificationRead next24Inheritance of Epigenetic ChangesRead next25Polygenic Inheritance and Continuous VariationRead next26Environmental Effects on Polygenic TraitsRead next
Definition of Biodiversity
1Definition of BiodiversityRead next2Measuring Species RichnessRead next3Genetic Diversity and Heterozygosity IndexRead next4Calculating Index of DiversityRead next5Concept of EndemismRead next6Understanding Niches in EcosystemsRead next7Behavioral Adaptations of OrganismsRead next8Physiological Adaptations of OrganismsRead next9Anatomical Adaptations of OrganismsRead next10Natural Selection and AdaptationRead next11Mechanism of Evolution via Natural SelectionRead next12Hardy-Weinberg Equation UsageRead next13Reproductive Isolation and SpeciationRead next14Classification Based on Phenotypes and GenotypesRead next15Three Domains of Life and Molecular PhylogenyRead next16Plant Cell UltrastructureRead next17Comparison of Plant and Animal CellsRead next18Structure and Function of StarchRead next19Structure and Function of CelluloseRead next20Cellulose Microfibrils and Hydrogen BondsRead next21Secondary Thickening in Plant Cell WallsRead next22Xylem Vessels and Their PropertiesRead next23Sclerenchyma Fibres and Their PropertiesRead next24Phloem Sieve Tubes and Their FunctionRead next25Importance of Water in PlantsRead next26Role of Nitrate Ions in PlantsRead next27Role of Calcium Ions in PlantsRead next28Role of Magnesium Ions in PlantsRead next29Drug Testing Protocols: Historical and ModernRead next30Conditions for Bacterial GrowthRead next31Antimicrobial Properties of PlantsRead next32Sustainability of Plant Fibres and StarchRead next33Oil-Based Plastics vs Plant-Based AlternativesRead next34Role of Zoos in ConservationRead next35Role of Seed Banks in ConservationRead next36Scientific Research in Conservation EffortsRead next37Captive Breeding ProgrammesRead next38Reintroduction Programmes for Endangered SpeciesRead next39Educational Outreach by Zoos and Seed BanksRead next
Defining Ecosystem, Community, Population, Habitat
1Defining Ecosystem, Community, Population, HabitatRead next2Biotic and Abiotic Factors in HabitatsRead next3The Concept of Niche in EcologyRead next4Using Quadrats and Transects in EcologyRead next5Abiotic Factor Measurements in FieldworkRead next6Stages of Succession in EcosystemsRead next7Photosynthesis Overview and Energy StorageRead next8Phosphorylation and Hydrolysis of ATPRead next9Light-Dependent Reactions in PhotosynthesisRead next10Role of Chlorophyll in Electron ExcitationRead next11Photophosphorylation and NADP ReductionRead next12Photolysis of Water and Oxygen ProductionRead next13Light-Independent Reactions and Carbon FixationRead next14Calvin Cycle: GP, GALP, RuBP, RUBISCORead next15Biological Molecules Produced by PhotosynthesisRead next16Structure of Chloroplasts in PhotosynthesisRead next17Investigating Photosynthesis: The Hill ReactionRead next18Gross and Net Primary Productivity CalculationsRead next19Efficiency of Energy Transfers Between Trophic LevelsRead next20Evidence for Climate Change: Carbon Dioxide LevelsRead next21Temperature Records and Climate ChangeRead next22Pollen in Peat Bogs and Dendrochronology EvidenceRead next23Greenhouse Gases and Anthropogenic Climate ChangeRead next24Extrapolating Data for Climate PredictionsRead next25Limitations in Climate Change ModelsRead next26Effects of Climate Change on Plants and AnimalsRead next27Temperature and Enzyme Activity in OrganismsRead next28Gene Mutation and Natural Selection in EvolutionRead next29Proteomics and Genomics Supporting Evolution TheoryRead next30Peer Review and Scientific Journals in Evolution EvidenceRead next31Isolation and Gene Flow in SpeciationRead next32Allopatric and Sympatric Speciation MechanismsRead next33Temperature Effects on Enzyme-Catalysed ReactionsRead next34Investigating Temperature Effects on Organism DevelopmentRead next35Controversies in Climate Change ConclusionsRead next36Understanding the Carbon CycleRead next37Reforestation to Reduce Atmospheric Carbon DioxideRead next38Sustainable Resource Use and BiofuelsRead next39Balancing Human Needs and ConservationRead next
Determining Time of Death
1Determining Time of DeathRead next2Stages of DecompositionRead next3Role of Microorganisms in DecayRead next4Forensic EntomologyRead next5Muscle Contraction After DeathRead next6DNA Profiling TechniquesRead next7Polymerase Chain Reaction (PCR)Read next8Gel Electrophoresis for DNA AnalysisRead next9Structure of BacteriaRead next10Structure of VirusesRead next11How TB Infects Human CellsRead next12How HIV Infects Human CellsRead next13Non-Specific Immune ResponsesRead next14Inflammation and Lysozyme ActionRead next15Role of Interferons in ImmunityRead next16Phagocytosis MechanismRead next17Antigens and AntibodiesRead next18Plasma Cells and MacrophagesRead next19Antigen-Presenting CellsRead next20Role of B Cells in ImmunityRead next21Role of T Cells in ImmunityRead next22Post-Transcriptional Changes to mRNARead next23Pathogen Entry RoutesRead next24Body Barriers to InfectionRead next25Gut and Skin Flora ProtectionRead next26Types of ImmunityRead next27Natural and Artificial ImmunityRead next28Active and Passive ImmunityRead next29Evolutionary Race Between Pathogens and HostsRead next30Pathogen Evasion MechanismsRead next31Bacteriostatic vs Bactericidal AntibioticsRead next32Hospital Acquired InfectionsRead next33Antibiotic Prescription PracticesRead next34Infection Prevention in HospitalsRead next35Investigating Antibiotic Effects on BacteriaRead next36Ethical Use of DNA ProfilingRead next37Scientific Validation of Forensic TechniquesRead next
Muscles and Movement Basics
1Muscles and Movement BasicsRead next2Antagonistic Muscle PairsRead next3The Sliding Filament TheoryRead next4Role of Calcium Ions in Muscle ContractionRead next5ATP and ATPase in Muscle ContractionRead next6Aerobic Respiration OverviewRead next7Enzymes in RespirationRead next8Glycolysis ProcessRead next9Anaerobic Respiration and LactateRead next10Link Reaction and Krebs CycleRead next11Oxidative Phosphorylation and ChemiosmosisRead next12ATP Synthase FunctionRead next13Fate of Lactate Post-Anaerobic RespirationRead next14Cardiac Muscle Myogenic NatureRead next15Electrical Activity of the HeartRead next16Sinoatrial Node and Atrioventricular NodeRead next17Bundle of His and Purkyne FibresRead next18Electrocardiograms (ECGs) in Heart DiagnosisRead next19Calculating Cardiac OutputRead next20Ventilation and Cardiac Output in ExerciseRead next21Control of Heart and Ventilation RatesRead next22Medulla Oblongata in Cardiovascular ControlRead next23Spirometer Traces and Respiratory MetricsRead next24Structure of Muscle FibresRead next25Fast Twitch vs Slow Twitch Muscle FibresRead next26Negative Feedback MechanismsRead next27Positive Feedback MechanismsRead next28Dynamic Equilibrium in ExerciseRead next29Role of Hypothalamus in HomeostasisRead next30Mechanisms of ThermoregulationRead next31Exercise and Joint Wear and TearRead next32Exercise and Immune System EffectsRead next33Exercise and Obesity RiskRead next34Exercise and Cardiovascular Disease RiskRead next35Exercise and Diabetes RiskRead next36Keyhole Surgery in Sports MedicineRead next37Prostheses for Sports ParticipationRead next38Ethics of Performance-Enhancing SubstancesRead next39DNA Transcription Factors and HormonesRead next
Structure and Function of Sensory Neurones
1Structure and Function of Sensory NeuronesRead next2Structure and Function of Relay NeuronesRead next3Structure and Function of Motor NeuronesRead next4Role of Schwann Cells and MyelinationRead next5Stimulus Response in Nervous SystemsRead next6Pupil Dilation and Contraction MechanismRead next7Action Potential Conduction in AxonsRead next8Membrane Permeability to Ions in Nerve ImpulsesRead next9Role of Myelination in Saltatory ConductionRead next10Structure and Function of SynapsesRead next11Role of Neurotransmitters in Synaptic TransmissionRead next12Acetylcholine in Synaptic TransmissionRead next13Detection of Stimuli by Rod Cells in MammalsRead next14Role of Rhodopsin in VisionRead next15Opsin and Retinal in Light DetectionRead next16Hyperpolarisation of Rod CellsRead next17Action Potentials in Optic NeuronesRead next18Phytochrome in Plant Responses to LightRead next19IAA in Plant Growth and DevelopmentRead next20Nervous and Hormonal Coordination in AnimalsRead next21Cerebral Hemispheres: Location and FunctionRead next22Hypothalamus: Location and FunctionRead next23Cerebellum: Location and FunctionRead next24Medulla Oblongata: Location and FunctionRead next25MRI in Brain Structure InvestigationRead next26fMRI in Brain Function InvestigationRead next27PET Scans in Medical DiagnosisRead next28CT Scans in Brain ImagingRead next29Critical Period in Visual DevelopmentRead next30Animal Models in Brain Development ResearchRead next31Hubel and Wiesel’s ExperimentsRead next32Ethical Issues in Animal ResearchRead next33Learning by Habituation in AnimalsRead next34Investigating Habituation to StimuliRead next35Role of Dopamine in Parkinson’s DiseaseRead next36Role of Serotonin in DepressionRead next37Development of Drugs for Brain Chemical ImbalancesRead next38Effects of Drugs on Synaptic TransmissionRead next39Use of L-Dopa in Parkinson’s Disease TreatmentRead next40Action of MDMA in EcstasyRead next41Genome Sequencing in Personalised MedicineRead next42Ethical Issues in Genome SequencingRead next43Producing Drugs Using GM OrganismsRead next44Risks of Using Genetically Modified OrganismsRead next45Benefits of Using Genetically Modified OrganismsRead next46Nature vs. Nurture in Brain DevelopmentRead next47Evidence from Newborn Abilities in Brain StudiesRead next48Animal Experiments in Brain Development ResearchRead next49Studies of Individuals with Brain DamageRead next50Twin Studies in Brain Development ResearchRead next51Cross-Cultural Studies in Brain DevelopmentRead next
Introduction to Practical Endorsement
1Introduction to Practical EndorsementRead next2Purpose of Practical Skills AssessmentRead next3Overview of the 18 Core PracticalsRead next4Common Practical Assessment Criteria (CPAC)Read next5Keeping Accurate Practical RecordsRead next6Authenticity in Practical WorkRead next7Collaboration in Practical ActivitiesRead next8Safety in Practical WorkRead next9Risk Assessment in Practical ActivitiesRead next10Using Apparatus and Instruments SafelyRead next11Making Accurate ObservationsRead next12Recording and Reporting FindingsRead next13Researching and Referencing in Practical WorkRead next14Planning Practical InvestigationsRead next15Controlling Variables in ExperimentsRead next16Using ICT in Practical WorkRead next17Developing Investigative ApproachesRead next18Appendix 5b: Practical Skills for Direct AssessmentRead next19Appendix 5c: Use of Apparatus and TechniquesRead next20Mapping Core Practicals to Appendix 5c RequirementsRead next21Monitoring Practical CompetencyRead next22Teacher Assessments for Practical CompetencyRead next23Minimum Practical Activities RequirementRead next24Evidence of Practical CompetencyRead next25Practical Competency Authentication SheetRead next26Assessment of Practical Skills in Written ExamsRead next27Exam Questions Assessing Practical SkillsRead next28Role of Teachers in Practical Skill DevelopmentRead next29Practical Skills and Scientific MethodsRead next30Ethical Considerations in Practical WorkRead next31Evaluating Practical MethodologiesRead next32Measurement Uncertainty and ErrorsRead next33Graphing and Data Analysis in Practical WorkRead next34Significant Figures in Practical DataRead next35Understanding Experimental Methods in ExamsRead next36Designing Additional Practical ActivitiesRead next37Role of Practical Work in Scientific Decision MakingRead next38Role of Practical Work in Validating New KnowledgeRead next39Practical Work and Ethical Use of Live SubjectsRead next40Practical Work and Safe Disposal of MaterialsRead next41Practical Work and Communication SkillsRead next42Practical Work and ICT ApplicationsRead next43Teacher Monitoring VisitsRead next44Malpractice in Practical AssessmentsRead next45Teacher Feedback on Practical CompetencyRead next46Role of JCQ in Monitoring Practical AssessmentsRead next47Pass/Fail Criteria for Practical EndorsementRead next48Practical Competency and Overall Qualification GradeRead next49Importance of Practical Work in BiologyRead next50Developing Confidence with Practical TechniquesRead next51Scientific Questions in Experimental ActivitiesRead next
The Heart and Blood Vessels
1The Heart and Blood VesselsRead next2Gas Exchange Surfaces and Fick’s LawRead next3Cell Structure, Organelles and Microscopy SkillsRead next4Measuring Biodiversity and Genetic DiversityRead next5Ecosystems, Communities and Food WebsRead next6Forensics: Time of Death and DecompositionRead next7ATP Demand, Muscle Contraction and PerformanceRead next8Neurones and Action PotentialsRead next9Cardiac Cycle, Cardiac Output and Blood PressureRead next10The Mammalian Lung: Ventilation and Gas ExchangeRead next11The Cell Cycle and MitosisRead next12Niche, Adaptation and Natural SelectionRead next13Factors Affecting Distribution and AbundanceRead next14Microorganisms, Decomposition and Carbon RecyclingRead next15Aerobic and Anaerobic Respiration in MuscleRead next16Synapses, Neurotransmitters and DrugsRead next17Blood Clotting and Cardiovascular DiseaseRead next18Cell Membranes and the Fluid Mosaic ModelRead next19Meiosis and Sources of Genetic VariationRead next20Evolution, Speciation and Hardy–WeinbergRead next21Core Practical 10: Ecology Fieldwork (Quadrats, Transects, Abiotic Factors)Read next22DNA Profiling and Genetic RelationshipsRead next23Core Practical 16: Measuring Respiration RateRead next24The Eye and Vision: Retina to Visual CortexRead next25Carbohydrates and Lipids in Diet and HealthRead next26Transport Across Membranes: Diffusion to Active TransportRead next27Fertilisation, IVF and Stem CellsRead next28Classification and Molecular Phylogeny (Three Domains)Read next29Succession and Climax CommunitiesRead next30PCR and DNA AnalysisRead next31Gas Exchange and Oxygen Transport During ExerciseRead next32Brain Regions and Brain ImagingRead next33Proteins, Enzymes and Biological RolesRead next34Osmosis and Water PotentialRead next35Cell Differentiation and Tissue OrganisationRead next36Plant Cells: Ultrastructure, Starch and CelluloseRead next37Photosynthesis: Light-Dependent and Light-Independent ReactionsRead next38Core Practical 14: Gel Electrophoresis of DNA FragmentsRead next39Control of Heart Rate and Ventilation (Negative Feedback)Read next40Coordinating Responses: Sensory Processing and ReflexesRead next41Energy Budgets, BMI and Waist-to-Hip RatioRead next42Enzymes in Living Systems (Factors Affecting Rate)Read next43Gene Expression and Cell SpecialisationRead next44Plant Transport Tissues and Structural SupportRead next45Core Practical 11: Hill Reaction and Photosynthesis RateRead next46Pathogens: Bacteria, Viruses and TransmissionRead next47ECGs and the Heart’s Electrical SystemRead next48Brain Development: Nature vs Nurture EvidenceRead next49Interpreting Risk: Correlation, Causation and Health DataRead next50Core Practical 3: Membrane PermeabilityRead next51Epigenetics: Environment, Gene Switching and PhenotypeRead next52Core Practical 6: Plant Stem Tissues Under the MicroscopeRead next53Energy Transfers: NPP, Biomass and Trophic EfficiencyRead next54Barriers, Inflammation and PhagocytosisRead next55Cardiac Output, Blood Pressure and Athletic PerformanceRead next56Learning, Memory and PlasticityRead next57Core Practical 1: Caffeine and Daphnia Heart RateRead next58Core Practical 4: Enzyme and Substrate ConcentrationRead next59Polygenic Inheritance and Continuous VariationRead next60Core Practical 7: Mineral Deficiencies in PlantsRead next61Climate Change Evidence and Anthropogenic CausesRead next62Adaptive Immunity: Antibodies, Memory Cells and VaccinesRead next63Thermoregulation and Homeostasis in ExerciseRead next64Core Practical 18: Investigating HabituationRead next65Core Practical 2: Vitamin C in Food and DrinkRead next66Nucleic Acids: DNA/RNA Structure and FunctionRead next67Core Practical 5: Root Tip Squash to Observe MitosisRead next68Core Practical 8: Investigating Fibre StrengthRead next69Climate Change Impacts, Models and Mitigation (Carbon Cycle Links)Read next70Antibiotics, Resistance and Infection ControlRead next71Core Practical 17: Spirometer Data and Exercise ResponsesRead next72Brain Chemistry and Parkinson’s DiseaseRead next73DNA Replication, Mutations and Cystic FibrosisRead next74Core Practical 9: Antimicrobials and Aseptic TechniqueRead next75Core Practical 12: Temperature and Enzyme ActivityRead next76Core Practical 15: Testing Antibiotics on BacteriaRead next77Sports Science: Training, Recovery, Technology and DopingRead next78Human Genome Project, Genetic Engineering and BioethicsRead next79Inheritance, Genetic Screening and EthicsRead next80Using Biology to Manage Resources: Drug Testing, Zoos and Seed BanksRead next81Core Practical 13: Temperature and DevelopmentRead next
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