567 simulations
Interactive simulations
Lumi has 567 free interactive simulations for NEET and JEE, across 106 NCERT chapters of Class 11 and 12: 187 in Physics, 115 in Chemistry, 180 in Biology and 85 in Maths. Each one is a picture you control: move a slider, drag a point or change a value, and the idea responds. Every simulation sits inside a lesson, so you can read the idea and then try it.
Physics
187 simulationsUnits and Measurements · Class 11
6Which digits does the calculator really know?In: Arithmetic with significant figuresPercentage errors add when you multiplyIn: Uncertainty in calculated resultsRead a vernier callipers and a screw gaugeIn: Uncertainty in calculated resultsA power multiplies the errorIn: Uncertainty in calculated resultsBuild a quantity from its dimensionsIn: Dimensions and dimensional formulaeFind the pendulum's formula from dimensions aloneIn: Deducing relations by dimensions
Motion in a Straight Line · Class 11
7Average speed is not the average of the speedsIn: Background: position, displacement and distance (prerequisite recap)Negative acceleration, faster car?In: AccelerationPosition, velocity and the graphs that record themIn: Reading motion graphsDraw a v–t graph, read the motionIn: Reading motion graphsThrown up, coming down: one acceleration all the wayIn: Free fall and vertical motion under gravityDistance in the nth secondIn: Free fall and vertical motion under gravityStopping distance: thinking, then brakingIn: Stopping distance and reaction time
Motion in a Plane · Class 11
6Resolve a vector: which part gets the cos?In: Resolving vectors into componentsAdding two displacements at an angleIn: Adding vectors analyticallyCrossing a riverIn: Adding vectors analyticallyDropped or thrown: which lands first?In: Constant acceleration in a planeThrow the ball: speed and angleIn: Projectile motionWhy constant speed still means accelerationIn: Uniform circular motion
Laws of Motion · Class 11
10Same change in momentum, different forceIn: Newton's second law, momentum and impulseExplosion: equal momenta, unequal energiesIn: Conservation of momentumA weight on two stringsIn: Equilibrium of a particleHeavier or lighter in a lift?In: Common forces in mechanicsStatic friction adjusts itself, up to a limitIn: FrictionWhat pushes the crate forward?In: FrictionWhat keeps a car on a banked curveIn: Circular motionWho supplies the centripetal force?In: Circular motionFriction is not always μNIn: Solving problems in mechanicsConnected bodies: one a, two free-body diagramsIn: Solving problems in mechanics
Work, Energy and Power · Class 11
8Work: only the part of the force along the motion countsIn: WorkWork is the area under F–xIn: Work done by a variable forceSame ends, different pathsIn: Potential energy and conservative forcesWhere does the energy go on a rough patch?In: Conservation of mechanical energyRound a vertical circleIn: Conservation of mechanical energyA spring stores ½kx², the area under its F–x lineIn: Potential energy of a springPower and speed: P = FvIn: PowerCollisions: momentum always survives, kinetic energy may notIn: Collisions
System of Particles and Rotational Motion · Class 11
11Rolling race down an inclineIn: Rigid bodies and their motionVelocities on a rolling wheelIn: Rigid bodies and their motionFind the centre of massIn: Centre of massExploding shellIn: Motion of the centre of massThe vector product in 3DIn: Vector product of two vectorsPushing a doorIn: Torque and angular momentumLadder against a smooth wallIn: Equilibrium of a rigid bodySee-saw: balance the momentsIn: Principle of moments and centre of gravitySame body, different axisIn: Moment of inertiaSpinning up a flywheelIn: Dynamics of rotationSpin chair: pull in, spin upIn: Angular momentum and its conservation
Gravitation · Class 11
7Equal areas in equal timesIn: The law of areasWhere the pulls cancelIn: Universal law of gravitationBuild a planetIn: Acceleration due to gravityg inside and outside the earthIn: g above and below the surfaceClimbing out of a gravity wellIn: Escape speedLaunch speed: fall, orbit or escapeIn: Earth satellitesSatellite dashboardIn: Earth satellites
Mechanical Properties of Solids · Class 11
4Mechanical Properties of Fluids · Class 11
8Pressure depends only on depthIn: Pascal's law and pressure with depthU-tube with two liquidsIn: Atmospheric and gauge pressureHydraulic lift: a small push, a large forceIn: Hydraulic machinesVenturi tube: speed up, pressure downIn: Bernoulli's principleTorricelli's jet: which hole squirts farthest?In: Bernoulli's principleTerminal velocity: when the forces balanceIn: Viscosity and Stokes' lawDrops and bubbles: why the small one pushes harderIn: Angle of contact, drops and bubblesCapillary riseIn: Capillary rise
Thermal Properties of Matter · Class 11
7Heat a plate with a holeIn: Thermal expansionA lake in winterIn: Anomalous expansion of water and thermal stressIce in warm water: does it all melt?In: CalorimetryHeating curve: where the heat goesIn: Latent heatTwo rods in series: finding the junction temperatureIn: ConductionBlackbody spectrumIn: Radiation and blackbody radiationNewton's law of coolingIn: Newton's law of cooling
Thermodynamics · Class 11
4Kinetic Theory · Class 11
5Two flasks joined by a stopcockIn: Partial pressures and the size of a moleculePressure from molecules hitting the wallsIn: Pressure of an ideal gas from molecular impactsrms speed: same energy, different speedsIn: Kinetic interpretation of temperatureDegrees of freedom decide a gas's specific heatIn: Specific heats of gasesMean free path: follow one moleculeIn: Mean free path
Oscillations · Class 11
6SHM as the shadow of a particle on a circleIn: SHM as the shadow of uniform circular motionBlock on a spring: what sets the period?In: Force law for SHM: F = −kxTwo springs, one blockIn: Force law for SHM: F = −kxIs it SHM? Plot a against xIn: Force law for SHM: F = −kxEnergy in SHM: where K equals UIn: Energy in SHMSimple pendulum: length, g and small swingsIn: The simple pendulum
Waves · Class 11
5Reading a travelling wave: y = a sin(kx − ωt)In: Displacement relation of a progressive waveReflection at a fixed end and a free endIn: Reflection and standing wavesA string fixed at both ends: which notes can it play?In: Harmonics of strings and pipesOrgan pipes: which notes fit in the air column?In: Harmonics of strings and pipesBeats: tuning one string against anotherIn: Beats
Electric Charges and Fields · Class 12
7Coulomb's law between two charged spheresIn: Coulomb's lawAdding the forces from several chargesIn: Forces between multiple chargesField lines of two chargesIn: Electric field linesHow fast a dipole's field falls offIn: Electric dipoleTorque on a dipole in a uniform fieldIn: Dipole in a uniform external fieldFlux through a closed surfaceIn: Gauss's lawFields from Gauss's lawIn: Applications of Gauss's law
Electrostatic Potential and Capacitance · Class 12
7A map of electric potentialIn: Equipotential surfacesAssembling charges, one at a timeIn: Potential energy of a system of chargesTwo conducting spheres joined by a wireIn: Electrostatics of conductorsA parallel plate capacitor on a 100 V batteryIn: Effect of dielectric on capacitanceA dielectric slab, battery on or offIn: Effect of dielectric on capacitanceCapacitors in series and in parallelIn: Combination of capacitorsCharge sharing and the lost energyIn: Energy stored in a capacitor
Current Electricity · Class 12
10Stretch a wire and watch its resistanceIn: Electric currents in conductors and Ohm's lawHow fast do electrons really move in a wire?In: Electron drift and where resistivity comes fromResistivity as temperature changesIn: Resistivity of materials and its temperature dependenceTwo bulbs on the mainsIn: Electrical energy and powerWhy the terminal voltage is less than the emfIn: Cells, emf and internal resistanceTwo cells: in series, in parallel, and one reversedIn: Cells in series and in parallelHow current divides between branchesIn: Kirchhoff's rulesWalking round a loop with KirchhoffIn: Kirchhoff's rulesBalance a Wheatstone bridgeIn: Wheatstone bridgeMetre bridge: find the unknown resistanceIn: Wheatstone bridge
Moving Charges and Magnetism · Class 12
10The force on a moving chargeIn: Magnetic field and the Lorentz forceFloating a rod on the magnetic forceIn: Force on a current-carrying conductorAn electron beam in a magnetic fieldIn: Motion in a magnetic fieldA charge spiralling along a magnetic fieldIn: Motion in a magnetic fieldField at the centre of an arcIn: Field on the axis of a circular loopInside and outside a thick wireIn: Ampere's circuital lawThe field inside a solenoidIn: The solenoidTwo parallel currentsIn: Force between parallel currentsTorque on a coil in a magnetic fieldIn: Torque on a current loopFrom galvanometer to ammeter and voltmeterIn: The moving coil galvanometer
Magnetism and Matter · Class 12
4Electromagnetic Induction · Class 12
7Three ways to change the fluxIn: Faraday's law of inductionLenz's law: push and pull a magnetIn: Lenz's law and conservation of energyA loop crossing a strip of fieldIn: Lenz's law and conservation of energyA rod sliding on railsIn: Motional emfEmf of a rotating rodIn: Rotating rods and wheelsA coil's back emfIn: Self-inductance and magnetic energyA coil turning in a fieldIn: AC generator
Alternating Current · Class 12
7Why 220 V mains peaks at 311 VIn: RMS values and average powerWhich leads: V or I?In: AC through an inductorReactance of a coil and a capacitorIn: AC through a capacitorAdding the voltages in a series LCR circuitIn: Series LCR circuit and impedanceTuning a series LCR circuitIn: ResonancePower factor: where does the power go?In: Power factorAn ideal transformerIn: Transformers
Electromagnetic Waves · Class 12
5Displacement current in a charging capacitorIn: Displacement currentA plane electromagnetic waveIn: Nature of electromagnetic wavesWhich way does the wave go?In: Nature of electromagnetic wavesAn em wave entering a mediumIn: Speed in vacuum and in mediaWalk the electromagnetic spectrumIn: The electromagnetic spectrum
Ray Optics and Optical Instruments · Class 12
9Spherical mirror: where the image formsIn: The mirror equation and magnificationSnell's law, the critical angle and total internal reflectionIn: Total internal reflectionThin lens: the same drag, a different formulaIn: Thin lenses: lens maker's formula and thin lens formulaA lens in a liquidIn: Thin lenses: lens maker's formula and thin lens formulaTwo thin lensesIn: Power of a lens and combinations of thin lensesPrism: the angle of minimum deviationIn: Refraction through a prismThin prism: deviation and coloursIn: Refraction through a prismCompound microscopeIn: Simple and compound microscopeAstronomical telescopeIn: Telescope
Wave Optics · Class 12
6Huygens wavelets at a boundaryIn: Refraction of a plane waveCoherent and incoherent additionIn: Coherent and incoherent additionYoung's double-slit fringesIn: Young's double-slit experimentYoung's fringes: colour and mediumIn: Young's double-slit experimentDiffraction at a single slitIn: Diffraction at a single slitPolaroids and Malus' lawIn: Malus' law and crossed polaroids
Dual Nature of Radiation and Matter · Class 12
5Atoms · Class 12
6Counting alpha-particles behind the foilIn: Alpha-particle scatteringAlpha-particle scatteringIn: Alpha-particle trajectoryBohr orbits: how r, v and E scale with n and ZIn: Bohr's postulatesElectrons into hydrogen: which lines light up?In: Energy levelsHydrogen's line spectrumIn: Line spectra of hydrogenDe Broglie's wave round an orbitIn: De Broglie's explanation
Nuclei · Class 12
5Doping: electrons and holesIn: Carrier concentration and band levelsHow the depletion layer formsIn: Formation of a p-n junctionp-n junction under biasIn: Diode under forward and reverse biasA one-way valve for currentIn: Diode V-I characteristicsFrom ac to steady dcIn: Half-wave and full-wave rectifiers
Chemistry
115 simulationsSome Basic Concepts of Chemistry · Class 11
4From grams to moles to atomsIn: The mole and molar massFrom mass per cent to a molecular formulaIn: Percentage composition, empirical and molecular formulaWhich reactant runs out first?In: Stoichiometry and the limiting reagentMolarity drifts with temperature, molality does notIn: Reactions in solutions: concentration terms
Structure of Atom · Class 11
8Fire alphas at gold foilIn: Thomson and Rutherford modelsBuild a nuclideIn: Atomic number, isotopes and isobarsLight that knocks out electronsIn: Planck's quantum theory and photoelectric effectBohr's ladder and hydrogen's linesIn: Bohr's model of the hydrogen atomOne electron, bigger nucleus: H, He⁺, Li²⁺, Be³⁺In: Bohr's model of the hydrogen atomCount an orbital's nodesIn: Shapes and energies of orbitalsWhy 4s fills before 3dIn: Shapes and energies of orbitalsFill the orbitals, one electron at a timeIn: Filling of orbitals and electronic configuration
From configuration to place in the tableIn: The s, p, d and f blocksHow big is an atom?In: Atomic and ionic radiiTen electrons, a growing nucleusIn: Atomic and ionic radiiPulling an electron offIn: Ionization enthalpyWhich atom welcomes an extra electron?In: Electron gain enthalpy and electronegativity
Chemical Bonding and Molecular Structure · Class 11
5Thermodynamics · Class 11
7The first law: a ledger of energyIn: Work, heat and the first lawSame start, same end, different workIn: Pressure-volume workBomb or open cup: ΔU or ΔH?In: CalorimetryHess's law: add the stepsIn: Hess's lawBonds broken, bonds formedIn: Enthalpies of combustion, atomisation, bonds, lattices, solution and dilutionEntropy is spreading outIn: Spontaneity and entropyWhen does a reaction go on its own?In: Gibbs energy and spontaneity
Equilibrium · Class 11
9Equilibrium is dynamicIn: Law of chemical equilibrium and KcHeating limestone in a closed vesselIn: Homogeneous and heterogeneous equilibria; KpAn ICE table for PCl₅In: Applications of K and the reaction quotientRolling downhill to equilibriumIn: K, Q and Gibbs energyPush an equilibrium and watch it push backIn: Factors affecting equilibria: Le Chatelier's principlepH of a strong acid and a weak acidIn: Ionisation of water, pH, weak acids and weak basesWhy some salt solutions are not neutralIn: Common ion effect and hydrolysis of saltsA buffer holds its pHIn: Buffer solutionsWhich salt dissolves more?In: Solubility equilibria of sparingly soluble salts
Redox Reactions · Class 11
4Counting σ and π bondsIn: Carbon's tetravalence and the shapes of organic moleculesFind the parent chain, then name itIn: IUPAC nomenclatureWhich intermediate is most stable?In: Electron displacement effectsThe inductive effect fades along a chainIn: Electron displacement effectsSteam distillation boils below 100 °CIn: Methods of purificationLassaigne's test for N, S and halogensIn: Qualitative analysis: detecting elements
Hydrocarbons · Class 11
3Solutions · Class 12
4What does the vapour over a mixture contain?In: Vapour pressure and Raoult's lawWhen does a mixture stop obeying Raoult's law?In: Ideal and non-ideal solutionsWhy does salt lower the freezing point more than it raises the boiling point?In: Depression of freezing pointWhat pressure stops water crossing a membrane?In: Osmosis and osmotic pressure
Electrochemistry · Class 12
3Chemical Kinetics · Class 12
8One reaction, three rates?In: Rate of a reactionCan you find a rate law from initial rates alone?In: Rate law and rate constantWhich plot turns the data into a straight line?In: First-order reactionsHow does a reactant run out: steadily or by halves?In: Half-life and pseudo first orderDo half-lives shrink, stay or grow?In: Half-life and pseudo first orderWhy does a little heat speed a reaction so much?In: Temperature and the Arrhenius equationWhat does a catalyst change, and what does it leave alone?In: Effect of a catalystIs a hard enough collision always enough?In: Collision theory
The d- and f-Block Elements · Class 12
7Which electrons leave first when a 3d atom forms an ion?In: Position and electronic configurationWhy is hafnium no bigger than zirconium?In: Physical properties and atomic sizeWhy is copper the odd one out?In: Electrode potentialsCounting unpaired electrons with a magnetIn: Magnetic propertiesWhere exactly does the pink stay?In: Potassium dichromate and permanganateDoes chromium change when the colour does?In: Potassium dichromate and permanganateHow many electrons does permanganate take?In: Potassium dichromate and permanganate
Coordination Compounds · Class 12
7How many chlorides can silver find?In: Werner's theoryCount the ligands or the donor atoms?In: Coordination number and oxidation numberBuild coordination isomers and turn them in 3DIn: Geometrical and optical isomerismWhich orbitals does the metal use: inner d or outer d?In: Valence bond theoryPair up or climb the gap?In: Crystal field theorySame ligands, different shape: does the split change?In: Crystal field theoryHow does the ligand set the colour of a complex?In: Colour in coordination compounds
Haloalkanes and Haloarenes · Class 12
7Which C–X bond is the most polar?In: The carbon-halogen bondDoes doubling the nucleophile double the rate?In: SN1 and reactivity orderWhere does the positive charge go?In: SN1 and reactivity orderWhich way does the product face?In: Stereochemistry of substitutionWhich β-hydrogen goes?In: Elimination and reactions with metalsCan Wurtz make any alkane you like?In: Elimination and reactions with metalsWhere should the nitro group sit?In: Reactions of haloarenes
Alcohols, Phenols and Ethers · Class 12
7Where do H and OH land?In: Preparing alcoholsCumene to phenol: where does the rest go?In: Preparing phenolsWhich phenol gives up its proton most easily?In: Acidity of alcohols and phenolsLucas test: which tube clouds first?In: Esterification, HX and dehydrationHow far can each alcohol be oxidised?In: Oxidation of alcoholsWilliamson synthesis: which pairing gives the ether?In: Preparing ethersWhich C–O bond does HI break?In: Ethers: properties and reactions
Aldehydes, Ketones and Carboxylic Acids · Class 12
7The oxidation ladderIn: Preparing aldehydes and ketonesCut the C=C: ozonolysis and hot KMnO₄In: Preparing aldehydes and ketonesGrignard reagent + carbonylIn: Nucleophilic additionWhy do aldehydes add nucleophiles faster?In: Nucleophilic additionWhich carbonyl compound passes which test?In: Oxidation and the testsAldol builderIn: α-Hydrogen reactions and usesHow strong is each acid?In: Physical properties and acidity
Amines · Class 12
7Count the carbonsIn: Gabriel and Hoffmann methodsHow basic is each amine?In: Basic character of aminesGas phase or water: the basicity order flipsIn: Basic character of aminesWhat a ring group does to aniline's lone pairIn: Basic character of aminesWhich amine passes which test?In: Nitrous acid and Hinsberg's reagentNitrating anilineIn: Electrophilic substitution in anilineKeep the diazonium salt coldIn: Diazonium salts: making and handling
Biomolecules · Class 12
7D and L: a label for the drawing, not for the lightIn: D and L: relative configurationClosing the sugar ringIn: Ring forms of glucose and fructoseWhich sugar reduces Tollens' reagent?In: Disaccharides and the glycosidic linkInvert sugar: the reading falls through zeroIn: Disaccharides and the glycosidic linkZwitter ion: which form wins at each pHIn: Amino acidsWhat does heat undo in a protein?In: Peptides and the four levels of protein structureBuild the partner strandIn: Nucleic acids
Biology
180 simulationsThe Living World · Class 11
2Biological Classification · Class 11
4Plant Kingdom · Class 11
6Three ways two gametes meetIn: Algae: body and reproductionWhich alga can still catch light down here?In: Green, brown and red algaeWalk a moss through its lifeIn: Liverworts and mossesWhich phase is the plant you see?In: PteridophytesFrom free spores to a seedIn: Homospory, heterospory and the seed habitDoes a pine need a second tree?In: Gymnosperm cones, pollen and ovules
Animal Kingdom · Class 11
7How many ways can you cut it in half?In: Symmetry and germ layersBuild a body plan, layer by layerIn: Coelom, segmentation and notochordKey out a mystery animalIn: Coelom, segmentation and notochordHow water moves through a spongeIn: Sponges, cnidarians and comb jelliesChordate or not, and where the notochord goesIn: Chordates and non-chordatesStaying up without an air bladderIn: Jawless and jawed fishesHeart chambers and body temperatureIn: Amphibians and reptiles
Morphology of Flowering Plants · Class 11
7Grow a floral axisIn: Racemose and cymose inflorescenceHow many ways can you cut a flower in half?In: Flower whorls and symmetryWhere do the other whorls join?In: Ovary position on the thalamusSet the petals in the budIn: Calyx, corolla and aestivationJoin the stamensIn: AndroeciumWhere do the ovules sit?In: Gynoecium and placentationWrite a floral formulaIn: Floral formula and Solanaceae
Anatomy of Flowering Plants · Class 11
5Structural Organisation in Animals · Class 11
3Cell: The Unit of Life · Class 11
7Crossing the cell membraneIn: Eukaryotic cells and the cell membraneLayers of a plant cell wallIn: Cell wallThe secretory routeIn: Endomembrane system: ER and Golgi apparatusTwo membranes, two organellesIn: PlastidsCilium axoneme or centriole?In: Ribosomes, cytoskeleton, cilia, flagella and centriolesSvedberg units in a centrifugeIn: Ribosomes, cytoskeleton, cilia, flagella and centriolesWhere is the centromere?In: Nucleus and microbodies
Biomolecules · Class 11
8Acid-soluble and acid-insoluble fractionsIn: BiomacromoleculesThe iodine test for starchIn: PolysaccharidesNucleoside or nucleotide?In: Nucleic acidsBuilding a protein, level by levelIn: Structure of proteinsWhat does an enzyme change?In: How enzymes speed up reactionsWhat speeds an enzyme up or slows it down?In: Factors affecting enzyme activityMalonate against succinateIn: Factors affecting enzyme activityCo-factors: prosthetic group, co-enzyme, metal ionIn: Classification of enzymes and co-factors
Cell Cycle and Cell Division · Class 11
5Photosynthesis in Higher Plants · Class 11
7Engelmann's bacteriaIn: Pigments involved in photosynthesisThe Z schemeIn: Electron transport, splitting of water and photophosphorylationMaking ATP from a proton gradientIn: Chemiosmotic hypothesis of ATP synthesisThe Calvin cycle's ledgerIn: Use of ATP and NADPH: the Calvin cycle (C₃ pathway)The C₄ carbon pumpIn: The C₄ pathwayRuBisCO's choiceIn: PhotorespirationLimiting factors in photosynthesisIn: Factors affecting photosynthesis
Respiration in Plants · Class 11
5Plant Growth and Development · Class 11
6Arithmetic and geometric growthIn: Arithmetic and geometric growthAbsolute or relative growth?In: Absolute and relative growth rateCallus cultureIn: Differentiation, dedifferentiation and redifferentiationApical dominanceIn: AuxinsPlant growth regulator benchIn: Ethylene and abscisic acidABA against GAIn: Ethylene and abscisic acid
Breathing and Exchange of Gases · Class 11
6Breathing in by changing the chest's sizeIn: Mechanism of breathingReading a spirometer traceIn: Respiratory volumes and capacitiesGas exchange across the alveolar wallIn: Exchange of gasesThe oxygen dissociation curveIn: Transport of oxygenHow blood carries carbon dioxideIn: Transport of carbon dioxideWhat drives your breathingIn: Regulation of respiration
Body Fluids and Circulation · Class 11
7Matching blood for a transfusionIn: Blood groupsRh incompatibility in pregnancyIn: Blood groupsThe clotting cascadeIn: Coagulation of bloodTissue fluid and lymphIn: Lymph (tissue fluid)The heart's own pacemakerIn: The human heartOne turn of the cardiac cycleIn: The cardiac cycleHow much blood the heart pumpsIn: The cardiac cycle
Excretory Products and their Elimination · Class 11
6Which waste can this animal afford?In: Nitrogenous wastesShort loop, long loopIn: The nephronSqueeze plasma through the filterIn: Glomerular filtrationA day of filtrate, balancedIn: Reabsorption and secretionDown, up and down againIn: Counter current mechanismThree hormone loops on one kidneyIn: Regulation of kidney function
Locomotion and Movement · Class 11
5Neural Control and Coordination · Class 11
4Chemical Coordination and Integration · Class 11
7Two ways from the hypothalamus to the pituitaryIn: The pituitary glandIodine, TSH and the size of the thyroidIn: Pineal and thyroid glandsTwo hormones hold blood calcium steadyIn: Parathyroid gland and thymusInsulin and glucagon keep blood glucose steadyIn: PancreasLH and FSH run the testis and the ovaryIn: Testis and ovaryHormones from the gut and the heartIn: Hormones of heart, kidney and gutWhere does a hormone's receptor sit?In: Mechanism of hormone action
Sexual Reproduction in Flowering Plants · Class 12
5Building the embryo sacIn: The embryo sacDesign a flower for wind or for beesIn: Kinds of pollination and its agentsWhich devices stop selfing?In: Outbreeding devices and pollen-pistil interactionPloidy map of the fertilised ovuleIn: Double fertilisationEndosperm first, then the embryoIn: Endosperm and embryo
Human Reproduction · Class 12
5Hormones that run the testisIn: Gametogenesis: spermatogenesisOne oocyte, one ovum; one spermatocyte, four spermsIn: Gametogenesis: oogenesisHormones of the menstrual cycleIn: The menstrual cycleMeeting in the ampullaIn: Fertilisation and implantationHormones of pregnancyIn: Pregnancy and embryonic development
Reproductive Health · Class 12
3Principles of Inheritance and Variation · Class 12
7A one-gene cross in pea plantsIn: Inheritance of one gene: dominance and segregationDominance: complete, incomplete or co?In: Incomplete dominance, co-dominance and multiple allelesABO blood groups: who can have which child?In: Incomplete dominance, co-dominance and multiple allelesA two-gene cross: seed shape and colourIn: Inheritance of two genes: independent assortmentLinked genes and a genetic mapIn: Chromosomal theory, linkage and recombinationTracing a sex-linked trait through a familyIn: Genetic disorders: pedigree and Mendelian disordersNon-disjunction and the karyotypes it makesIn: Chromosomal disorders
Molecular Basis of Inheritance · Class 12
8Build a DNA double helixIn: The double helix and central dogmaPacking 2.2 m of DNA into a nucleusIn: Packaging of the DNA helixHershey and Chase: is it DNA or protein?In: The search for genetic materialMeselson and Stahl: how does DNA copy itself?In: ReplicationThe replication forkIn: ReplicationTemplate strand, coding strandIn: TranscriptionReading the genetic codeIn: The genetic code and mutationsThe lac operon switchIn: Regulation of gene expression: the lac operon
Evolution · Class 12
6One bone plan, four mammal limbsIn: Homology and analogyMoths on a trunk: natural selection in actionIn: Natural selection seen in actionDarwin's finches: one ancestor, many beaksIn: Adaptive radiationHardy-Weinberg: from allele frequency to genotypesIn: Mutation and the Hardy-Weinberg principleThree ways selection reshapes a bell curveIn: What disturbs the equilibriumGenetic drift: allele frequency changing by chanceIn: What disturbs the equilibrium
Human Health and Disease · Class 12
6The two-host life cycle of PlasmodiumIn: Malaria and amoebiasisImmune memory: primary and secondary responsesIn: Acquired immunityActive and passive immunity: fast but fading, or slow with memoryIn: Active and passive immunityA lymphocyte's journey: primary and secondary lymphoid organsIn: Lymphoid organsHIV: years of silent declineIn: AIDSContact inhibition, lostIn: Cancer
Microbes in Human Welfare · Class 12
4Biotechnology: Principles and Processes · Class 12
11Palindrome hunt: where a restriction enzyme can bindIn: Restriction enzymesSticky ends: cut with one enzyme, join with ligaseIn: Restriction enzymesAgarose gel electrophoresis: small fragments run fartherIn: Gel electrophoresispBR322: finding recombinants by replica platingIn: Cloning vectorsBlue-white screening: colourless colonies carry the insertIn: Cloning vectorsOnly DNA linked to an ori is copiedIn: Cloning vectorsHeat shock: getting DNA into E. coliIn: Plant and animal vectors, and competent hostsIsolating DNA: open the cell, clean up, spoolIn: Isolating and cutting DNAPCR: copies double every cycleIn: PCROne PCR cycle: set the three temperaturesIn: PCRBatch or continuous cultureIn: Inserting DNA and getting the product
Biotechnology and its Applications · Class 12
5Bt toxin: inactive in the bacterium, active in the insect gutIn: Bt cottonRNA interference: a double strand silences the nematode's mRNAIn: RNA interferenceHuman insulin: assembling the mature hormoneIn: Genetically engineered insulinADA gene therapy: why the lymphocytes must be topped upIn: Gene therapyCatch it before the symptomsIn: Molecular diagnosis
Organisms and Populations · Class 12
3Ecosystem · Class 12
6Gross and net primary productivityIn: ProductivityDecomposition of a bag of leaf litterIn: DecompositionFrom sunlight to herbivoresIn: Energy flowPyramid of energy: the 10 per cent lawIn: Trophic levels and the 10 per cent lawEcological pyramids: upright or inverted?In: Ecological pyramidsOne sparrow, two trophic levelsIn: Limits of trophic levels and pyramids
Biodiversity and Conservation · Class 12
4Maths
85 simulationsSets · Class 11
4Relations and Functions · Class 11
5Trigonometric Functions · Class 11
8What one radian looks likeIn: Radian measure and arc lengthSine and cosine on the unit circleIn: Sine and cosine on the unit circleAll six values from oneIn: Signs in the four quadrantsThe six graphs and their periodsIn: Domain, range and graphsWhy sin (A + B) is not sin A + sin BIn: Sine and cosine of sums and differencesAllied angles are mirror imagesIn: Allied anglestan (A + B) as the slope of a turned lineIn: Tangent and cotangent of sumsDoubling the angle is not doubling the valueIn: Double and triple angle formulas
Complex Numbers and Quadratic Equations · Class 11
5Powers of i go round in foursIn: Powers of iWhen √a × √b is not √(ab)In: Square roots of negative numbersMultiplying by the conjugate makes a real numberIn: Modulus and conjugatePoints of the Argand planeIn: The Argand planeWhere the roots go when D turns negativeIn: Quadratics with a negative discriminant
Linear Inequalities · Class 11
3Permutations and Combinations · Class 11
6Fill the places, then countIn: Permutations of distinct objectsGlue them together, or keep them apartIn: Arrangements with conditionsTag the twins, then take the tags offIn: Permutations with repeated objectsSelections, and the orders inside themIn: CombinationsPatterns in the table of nCrIn: Properties of combinationsWhere a word sits in the dictionaryIn: Selecting then arranging, and dictionary order
Binomial Theorem · Class 11
4Sequences and Series · Class 11
3Straight Lines · Class 11
4Conic Sections · Class 11
7Slice a double coneIn: Sections of a coneComplete the square, find the circleIn: The circleFocus, directrix and the parabolaIn: Parabola and its standard formsA string, two pins and an ellipseIn: Ellipse: foci and axesRead a and b off the equationIn: Standard equations of an ellipseA hyperbola keeps a constant differenceIn: Hyperbola: foci and axesWhy reflectors are parabolicIn: Conics in applied problems