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Animal cell organelles and what they doPlant cell organelles and what they doBacterial cell structure (prokaryotes) vs eukaryotesComparing animal, plant and bacterial cellsSpecialised cells and how structure links to functionLevels of organisation in multicellular organisms (cells → tissues → organs → systems)Using SI units and prefixes in biology (milli, micro, nano, pico)Estimating cell size and scale (orders of magnitude)Light microscopes: uses, limits and what you can seeElectron microscopes: why they give more detailCore Practical: Using a microscope to observe specimens and produce labelled scientific drawingsCalculating magnification, image size and real sizeUsing scale bars correctlyEnzymes as biological catalystsThe active site model (lock-and-key / induced fit idea at GCSE level)Enzyme specificity (why one enzyme fits one substrate)Effects of temperature on enzyme activityEffects of pH on enzyme activityEffects of substrate concentration on enzyme activityCore Practical: Investigating the effect of pH on enzyme activityInterpreting enzyme graphs and identifying optimum conditionsCalculating rates in enzyme experimentsDiffusion: definition and examples in cellsFactors affecting rate of diffusion (concentration gradient, surface area, distance, temperature)Osmosis: definition and why it’s specialOsmosis in animal vs plant cells (turgid, plasmolysed, lysed)Active transport: definition and where cells use itComparing diffusion, osmosis and active transportCore Practical: Investigating osmosis in potato cylindersCalculating percentage change in mass for osmosis dataFood tests: starch (iodine)Food tests: reducing sugars (Benedict’s)Food tests: proteins (biuret)Food tests: fats (ethanol emulsion test)Core Practical: Using chemical reagents to identify biological moleculesEnergy content in food (simple calorimetry) and evaluating limitations
The cell cycle overview (growth, DNA replication, division)Interphase: what happens and why it mattersMitosis stage-by-stage: prophaseMitosis stage-by-stage: metaphaseMitosis stage-by-stage: anaphaseMitosis stage-by-stage: telophaseCytokinesis and forming daughter cellsChromosomes, DNA and why daughter cells are genetically identicalWhy mitosis is needed for growth and repairMitosis in asexual reproductionCancer as uncontrolled cell divisionGrowth in animals: cell division and differentiationGrowth in plants: cell division, elongation and differentiationCell differentiation and specialised cellsUsing percentile charts to monitor human growthEmbryonic stem cells: what they are and what they can doAdult stem cells and plant meristemsStem cells in medicine: potential benefitsStem cells in medicine: risks and ethical issuesBrain regions: cerebrum, cerebellum and medulla oblongataCT scans: how they help study the brainPET scans: how they help study brain functionLimits of treating brain and nervous system damage (spinal injuries, brain tumours)Neurones: sensory, relay and motor (structures and roles)Synapses and neurotransmitters (how signals cross gaps)The reflex arc step-by-stepThe eye: cornea and lens (focusing)The eye: iris and pupil (controlling light entry)The eye: retina, rod cells and cone cellsEye defects: cataractsEye defects: long-sightedness and short-sightednessEye defects: colour blindnessCorrecting vision defects (lenses and cataract treatment)
Asexual reproduction: advantages and disadvantagesSexual reproduction: advantages and disadvantagesMeiosis: what it produces and why it creates variationHaploid vs diploid and what gametes areDNA as a polymer and why it’s called a polymerThe double helix and complementary base pairingNucleotides: sugar-phosphate backbone and basesGenome vs gene (clear definitions)Extracting DNA from fruit (method and why each step works)The genetic code: base order → amino acid orderProtein folding and why shape matters (enzyme shape)Transcription: making mRNA from DNATranslation: using mRNA at ribosomes to build proteinsCodons and how triplets code for amino acidstRNA and bringing amino acids to ribosomesNon-coding DNA variants: changing how much protein is madeCoding DNA variants: changing amino acid sequence and protein functionGregor Mendel’s work and why it was hard to accept at the timeAlleles as the reason inherited characteristics differKey inheritance terms (chromosome, gene, allele, genotype, phenotype, etc.)Monohybrid crosses using genetic diagramsPunnett squares: predicting offspring genotypes and phenotypesPedigree diagrams: tracking inheritance in familiesSex determination (XX/XY) using genetic diagramsCalculating inheritance outcomes (ratios, percentages, probability)ABO blood groups: codominance and multiple allelesSex-linked genetic disorders: how inheritance worksPolygenic inheritance (why most traits aren’t single-gene)Causes of variation: genetic vs environmentalHuman Genome Project: outcomes and medical applicationsGenetic variation in populations and mutation as the sourceMutation effects: no effect, small effect, rare large effects
Darwin and Wallace: what they contributed and why it matteredNatural selection: variation within populationsNatural selection: competition and selection pressuresNatural selection: survival and reproduction (fitness)Natural selection: inheritance and how traits spreadResistant organisms as evidence for evolution (antibiotic resistance)Fossil evidence for human evolution: ArdiFossil evidence for human evolution: LucyFossil evidence for human evolution: Leakey’s 1.6 million-year-old fossilsEvidence from stone tools: how tools changed over timeDating stone tools using their environment (context evidence)Pentadactyl limbs as evidence for evolution (homologous structures)Classification: why genetic analysis supports three domainsSelective breeding: how humans change populationsTissue culture: how it works and why it’s usefulTissue culture in medical research and plant breedingGenetic engineering: what it means (changing the genome)Genetic engineering: restriction enzymes and cutting DNAGenetic engineering: sticky ends and matching DNA fragmentsGenetic engineering: ligase and joining DNAGenetic engineering: vectors and transferring genesGM crops example: Bt gene for insect resistancePros and cons of GM organisms (including ethics)Fertilisers: boosting yields and potential drawbacksBiological control: how it works and risksWeighing benefits and risks of selective breeding and genetic engineering (agriculture + medicine)
Health as physical, mental and social wellbeing (WHO definition in context)Communicable vs non-communicable diseaseHow one disease can increase susceptibility to othersPathogens: viruses, bacteria, fungi and protistsCholera: cause, symptoms and transmission routeTuberculosis: cause, symptoms and airborne spreadChalara ash dieback: impact and spreadMalaria: protist disease and vector transmissionHIV: effect on immune system and AIDSStomach ulcers and Helicobacter (separate science)Ebola: key features and spread via body fluids (separate science)Reducing spread: hygiene, sanitation, isolation and vaccination (applied to examples)Viral lifecycles: lytic pathwayViral lifecycles: lysogenic pathwaySTIs: how chlamydia spreads and how to reduce spreadSTIs: HIV spread and prevention strategiesPlant defences: physical barriers (cuticle, cell wall)Plant defences: chemical defences and medicinal usesDetecting plant disease: field observation and diagnostic testingHuman physical barriers: skin, mucus and ciliaHuman chemical defences: lysozyme and stomach acidSpecific immune response: antigens and antibody productionMemory lymphocytes and the secondary immune responseVaccination using inactive pathogens (how it builds immunity)Immunisation: advantages, disadvantages and herd immunityWhy antibiotics treat bacterial infections but not viral infectionsAseptic technique in culturing microorganisms (incl. autoclaves and sterile tools)Core Practical: Effects of antiseptics/antibiotics/plant extracts on microbial culturesMeasuring inhibition zones and calculating areas (πr²)Stages of developing new medicines (discovery → trials)Preclinical testing vs clinical testing (what each checks)Producing monoclonal antibodies (lymphocytes → hybridoma)Uses of monoclonal antibodies: pregnancy testsUses of monoclonal antibodies: diagnosis and targeted treatmentAdvantages of monoclonals vs drugs/radiotherapy (targeting)Non-communicable disease as multi-factor (genes + lifestyle + environment)Lifestyle: diet and exercise links to obesity and malnutrition (BMI)Lifestyle: alcohol and liver diseaseLifestyle: smoking and cardiovascular diseaseTreating cardiovascular disease: medicationTreating cardiovascular disease: surgeryTreating cardiovascular disease: lifestyle change (evaluation)
Photosynthetic organisms as producers and the start of biomassPhotosynthesis word equation and symbol equationPhotosynthesis as an endothermic reaction (energy in)Limiting factors: light intensityLimiting factors: carbon dioxide concentrationLimiting factors: temperatureInteractions between limiting factors (shifting the limiting factor)Core Practical: Effect of light intensity on photosynthesis rateInverse square law and light intensity vs distance (applied to photosynthesis)Root hair cells: adaptations for absorptionXylem: structure and transporting water/mineral ionsPhloem: structure and transporting sucrose (needs energy)Transpiration: movement of water through the plantStomata and guard cells: structure and functionTranslocation: moving sugars around the plantLeaf structure: palisade layer, spongy mesophyll and air spacesLeaf structure: stomata distribution and gas exchangeLeaf structure: chloroplasts and light captureEnvironmental factors affecting water uptake (light, wind, temperature)Rate calculations for transpiration (interpreting change over time)Plant adaptations to extreme environments (leaf size/shape, cuticle, stomata)Auxins and control of growthPhototropism: how auxin causes shoots to bend to lightGravitropism: how auxin causes roots/shoots responsesCommercial uses of auxins (weedkillers, rooting powders)Commercial uses of gibberellins (germination, flowering, seedless fruit)Commercial uses of ethene (fruit ripening)
Endocrine system overview: hormones and target organsKey endocrine glands (pituitary, thyroid, pancreas, adrenal, ovaries, testes)Adrenaline and the fight-or-flight responseAdrenaline effects: heart rate, blood pressure and blood flow to musclesAdrenaline effects: raising blood glucose via glycogen → glucoseThyroxine and metabolic rateNegative feedback control using thyroxine (TRH, TSH, thyroxine loop)Menstrual cycle stages (uterus lining changes)Oestrogen: roles in the menstrual cycleProgesterone: roles in the menstrual cycleFSH and LH: roles and ovulationHormone interactions controlling menstruation and uterus liningHormonal contraception: how it prevents pregnancyBarrier contraception: how it prevents pregnancyEvaluating hormonal vs barrier contraceptionFertility treatment hormones: IVF steps overviewClomifene therapy: how it works (stimulating ovulation)Why a constant internal environment mattersHomeostasis overview: thermoregulation and osmoregulationThermoregulation: how temperature affects enzymesSkin structure for thermoregulation (dermis, epidermis)Hypothalamus as the thermoregulatory control centreThermoregulation responses: shiveringThermoregulation responses: vasoconstriction and vasodilationBlood glucose control: insulin roleBlood glucose control: glucagon roleType 1 diabetes: cause and control methodsType 2 diabetes: cause and control methodsBMI and waist:hip calculations (linking data to diabetes risk)Evaluating the correlation between body mass and type 2 diabetesUrinary system structure (kidneys, ureters, bladder, urethra)Nephron structure overview (Bowman’s capsule to collecting duct)Filtration at the glomerulus and Bowman’s capsuleSelective reabsorption of glucoseWater reabsorption and balancing water levelsADH and collecting duct permeabilityKidney failure treatments: dialysis vs transplantUrea formation from excess amino acids in the liver
Why organisms need transport systems (O₂, CO₂, nutrients, ions, water, urea)Exchange surfaces: what they are and why they’re neededSurface area to volume ratio and its consequencesAlveoli adaptations for diffusion (large SA, short distance, blood supply)Diffusion rate factors in exchange (surface area, gradient, distance)Using Fick’s law to calculate diffusion rate (separate science)Blood components: red blood cells and oxygen transportBlood components: white blood cells (phagocytes and lymphocytes)Blood components: plasma and what it carriesBlood components: platelets and clottingBlood vessels: arteries structure and functionBlood vessels: veins structure and functionBlood vessels: capillaries structure and functionHeart structure: chambers and valvesDouble circulatory system: pulmonary vs systemicWhy ventricle walls differ in thicknessCellular respiration: why cells need itAerobic respiration: reactants, products and energy releaseAnaerobic respiration: how it differs and when it happensComparing aerobic and anaerobic respirationCore Practical: Investigating respiration rate in living organismsHeart rate, stroke volume and cardiac output calculationsInterpreting exercise data for breathing rate and heart rate
Levels of organisation: organism to ecosystemAbiotic factors affecting communities (temperature, light, water, pollutants)Biotic factors affecting communities (competition, predation)Interdependence in communitiesParasitism and mutualism (with clear examples)Core Practical: Fieldwork using quadrats and belt transectsChoosing an appropriate sampling method (random vs along a gradient)Calculating means from field dataEstimating population size or abundance from quadrat dataUsing transect results to describe distribution patternsEnergy in ecosystems: producers, consumers and decomposersEnergy transfer losses at each trophic level (less useful forms)Pyramids of biomass: what they show and why shapes differCalculating efficiency of energy transfer between trophic levelsHuman impacts: fish farming (benefits and harms)Human impacts: non-indigenous species and biodiversityHuman impacts: eutrophication causes and effectsWhy biodiversity matters (local and global)Conservation strategies and reforestation impactsFood security: population growth and demandFood security: meat consumption and land useFood security: pests, pathogens and environmental changeSustainability issues (biofuels, cost of inputs)Material cycles overview (abiotic ↔ biotic)Carbon cycle processes and the role of decomposersWater cycle processes and potable water production (incl. desalination)Nitrogen cycle: nitrates, bacteria and plant uptakeFarming strategies: fertilisers and crop rotation (linked to nitrates)Indicator species for water pollution (clean vs polluted water)Indicator species for air quality (lichens, blackspot fungus)Decomposition: what it is and why it mattersDecomposition rate factors: temperature, water content, oxygenFood preservation explained using decomposition factorsComposting explained using decomposition factorsCalculating rate changes in decay of biological material
