Osmosis and Cell Tonicity
Adjust solute concentrations inside and outside a cell and watch water move across the membrane until the cell swells, shrinks or bursts.
~15 min
10 branches · 95 topics
All simulations
Every branch of the lab in one place. Open a live simulator or jump into a branch to see what is coming next.
Live now
Cell Structure and Organelles
Rotate and zoom an interactive 3D cell and click each organelle to learn what it does.
~12 min
Photosynthesis and the Light Reactions
Explore a leaf and a chloroplast, step through the light-dependent reactions and the Calvin cycle, and see how light, CO₂, water and temperature limit the rate.
~25 min
DNA Replication
Step through helicase, primase and DNA polymerase as a double helix copies itself.
~15 min
Natural Selection and Evolution
Change the environment and watch traits in a population shift across generations.
~15 min
Cellular Respiration and ATP Production
Watch glucose become ATP in the cytoplasm and mitochondria, step through glycolysis, the Krebs cycle and the electron transport chain, and see what happens when oxygen runs out.
~15 min
Mitosis and the Cell Cycle
Follow an animal cell through interphase and every stage of mitosis to two identical daughter cells, click its chromosomes and spindle, and compare mitosis with meiosis.
~15 min
Meiosis and Genetic Variation
Watch homologous chromosomes pair, cross over and separate through meiosis I and II, then flip their arrangement and make gametes to see how variation arises.
~15 min
Mendelian Genetics and Inheritance
Choose parent genotypes, build Punnett squares for one or two traits, and breed pea plants to compare predicted ratios with real chance.
~15 min
Ecosystem Energy Flow and Nutrient Cycling
Follow energy from the Sun through a meadow food web as it is lost as heat, watch decomposers recycle nutrients, and explore the carbon and nitrogen cycles.
~15 min
Atomic Structure
Add protons, neutrons and electrons and watch the element, charge and energy levels change.
~12 min
Chemical Bonding
Combine atoms into molecules and compare ionic and covalent bonds.
~15 min
Balancing Chemical Equations
Adjust coefficients and count atoms on both sides until mass is conserved.
~12 min
Acid-Base Reactions
Change pH and watch indicators, ion concentrations and neutralization respond.
~15 min
Reaction Rates
Vary temperature, concentration and surface area and measure how quickly particles react.
~15 min
States of Matter and Particle Motion
Heat and cool a particle model and watch it melt, freeze, evaporate, boil and condense.
~15 min
Gas Laws and Pressure
Squeeze, heat and fill a sealed cylinder and discover Boyle’s, Charles’s and the pressure–temperature law.
~15 min
Solutions, Solubility and Concentration
Dissolve salts and sugar, change the temperature and water, and see when a solution becomes saturated.
~15 min
Oxidation–Reduction and Electron Transfer
Watch electrons move in redox reactions, track oxidation states and identify oxidizing and reducing agents.
~15 min
Electrochemistry: Galvanic Cells and Electrolysis
Build a battery from two metals, then use electricity to split water and plate copper.
~20 min
Human Heart and Blood Circulation
Explore the chambers and valves of the heart and trace blood through both circuits.
~15 min
Respiratory System
Move the diaphragm, watch the lungs expand and follow oxygen into the blood.
~15 min
Human Skeletal System
Rotate a 3D skeleton, select bones and explore the joints that connect them.
~12 min
Nervous System and Neuron Firing
Stimulate a neuron and watch an action potential travel down the axon.
~15 min
Digestive System
Follow food from mouth to intestine and see where each nutrient is broken down and absorbed.
~12 min
Urinary System and Kidney Function
Follow blood through a nephron and see how the kidneys filter waste and balance water and salt.
~15 min
Human Reproductive System
Explore the female and male reproductive systems, the menstrual cycle hormones and the first days after fertilisation.
~15 min
Endocrine System and Hormonal Regulation
Explore the glands and their hormones, run the thyroid feedback loop and control blood glucose with insulin and glucagon.
~15 min
Immune System and Defence Against Disease
Explore the immune organs, let a pathogen in through a cut and watch innate and adaptive immunity respond, then compare first and second exposures.
~15 min
Muscular System and Muscle Contraction
Explore major skeletal muscles in 3D, watch actin and myosin slide inside a sarcomere, move the arm with an antagonistic pair and compare the three muscle types.
~15 min
Solar System Explorer
Compare planets, their orbits and their relative sizes in an interactive 3D model.
~12 min
Phases of the Moon
Move the Moon around the Earth and see which phase appears from the ground.
~12 min
Planetary Orbits and Gravity
Set mass, distance and speed and watch orbits become circles, ellipses or escape paths.
~15 min
Stellar Life Cycle
Choose a star’s mass and follow it from nebula to white dwarf, neutron star or black hole.
~15 min
Black Holes and Gravitational Lensing
Move a black hole across a star field and watch it bend the light passing nearby.
~15 min
Solar and Lunar Eclipses
Line up the Sun, Earth and Moon, see the umbra and penumbra, and find out why eclipses don’t happen every month.
~15 min
Seasons and Earth’s Axial Tilt
Move Earth around the Sun and compare sunlight angle and day length in the two hemispheres.
~15 min
Tides and the Earth–Moon–Sun System
Move the Moon around Earth and see how the Moon and Sun raise tides, from spring tides to neap tides.
~15 min
Exoplanets and the Transit Method
Send a planet across its star, measure the dip in starlight and find out which orbits we can detect.
~15 min
Cosmic Expansion and Redshift
Follow light across expanding space and watch its wavelength stretch into the red and infrared.
~15 min
Animal Classification
Sort animals using a branching key and discover the traits that define each group.
~12 min
Animal Cell vs. Plant Cell
Compare the two cell types side by side and toggle the structures that make them different.
~12 min
Animal Adaptations
Change temperature, food and predators and see which adaptations help animals survive.
~12 min
Food Chains and Food Webs
Add or remove species and watch the effects ripple through an ecosystem.
~12 min
Animal Locomotion
Explore the mechanics of walking, flying and swimming and the forces behind each.
~12 min
Animal Circulatory Systems
Compare open and closed circulation and single and double circuits in an insect, fish, frog and mammal.
~15 min
Animal Respiratory Systems and Gas Exchange
Compare fish gills, insect tracheae and mammal lungs and see how oxygen diffuses across respiratory surfaces.
~15 min
Animal Reproduction and Life Cycles
Step through the life cycles of a butterfly, grasshopper, frog and chicken, and compare ways animals reproduce.
~15 min
Animal Nervous System and Sensory Responses
Stimulate a neuron, follow a reflex arc step by step, and see how animals from hydra to cat detect and respond to stimuli.
~15 min
Animal Behavior and Biological Rhythms
Change temperature, day length, food and predators to see how a flock behaves, and explore daily rhythms, instinct and learning.
~15 min
Plant Cell Structure
Explore the cell wall, chloroplasts and central vacuole that make plant cells unique.
~12 min
Plant Anatomy
Investigate roots, stems, leaves and flowers and the job each one does.
~12 min
Transpiration
Change humidity, wind, light and temperature and measure water loss from leaves.
~15 min
Seed Germination
Control water, temperature and oxygen and see which seeds sprout.
~12 min
Plant Growth and Tropisms
Move the light source and tilt the pot to see how plants respond to light and gravity.
~12 min
Plant Adaptations and Environmental Survival
Grow cacti, water lilies, mangroves, flytraps and more side by side, change the conditions and see which adaptations keep each plant alive.
~15 min
Plant Diversity and Life Cycles
Sort mosses, ferns, conifers and flowering plants on an evolutionary tree, step through their life cycles and see why some need water to reproduce.
~15 min
Plant Reproduction: Pollination and Fertilisation
Take apart a 3D flower, carry pollen by hand, bee or wind, compare self- and cross-pollination, and follow the pollen tube to double fertilisation, seed and fruit.
~15 min
Plant Hormones and Growth Regulation
Turn auxin, gibberellin, cytokinin, ABA and ethylene up or down, cut off a shoot tip, add drought, and watch growth, stomata, ripening and tissue culture respond.
~20 min
Plant Defense and Plant–Pathogen Interactions
Inspect thorns, spines and trichomes on a 3D plant, infect a leaf to follow PTI, ETI, the hypersensitive response and SAR, and watch a plant fight off caterpillars.
~20 min
Newton’s Laws of Motion
Apply forces to objects of different masses and measure the acceleration.
~12 min
Projectile Motion
Change launch angle, speed and gravity and predict where the projectile will land.
~15 min
Pendulum Motion
Adjust length, mass and starting angle and measure the period of oscillation.
~15 min
Wave Interference
Overlap two waves and control frequency, amplitude and phase to see interference patterns.
~15 min
Electricity and Circuits
Build series and parallel circuits and measure voltage, current and resistance.
~15 min
Inclined Planes and Friction
Tilt a slope, drag a block onto it and watch static friction hold it or kinetic friction slow its slide.
~15 min
Rotational Motion, Torque and Angular Momentum
Push a wheel at different distances and angles, compare disks, rings and rods, and spin on a stool to see angular momentum conserved.
~20 min
Momentum and Collisions
Aim two pucks on an air table and compare elastic, inelastic and sticky collisions: momentum is always conserved, kinetic energy is not.
~15 min
Fluid Mechanics, Pressure and Buoyancy
Drop objects into a tank, change the fluid, and measure pressure with depth to see why things float, sink or hover.
~15 min
Geometric Optics: Reflection, Refraction and Lenses
Aim a laser at mirrors and glass, test Snell’s law and total internal reflection, and form real and virtual images with lenses.
~20 min
Plate Tectonics
Move plates and observe what happens at divergent, convergent and transform boundaries.
~15 min
Rock Cycle
Apply heat, pressure and weathering to turn rocks from one type into another.
~12 min
Earth’s Layers
Cut into a 3D Earth and compare the temperature, density and state of each layer.
~12 min
Weather and Atmospheric Conditions
Change temperature, pressure and humidity and watch clouds and precipitation form.
~15 min
Water Cycle
Control the sun and terrain and follow water through evaporation, condensation and runoff.
~12 min
Earthquakes and Seismic Waves
Make faults slip in 3D, compare P-, S- and surface waves, read seismograms and locate an epicenter from three stations.
~20 min
Volcanoes and Volcanic Eruptions
Cut open a 3D volcano, change magma silica, temperature and gas to switch between effusive and explosive eruptions, and map lava, ash, pyroclastic flows and lahars.
~20 min
Geological Time and Fossil Formation
Zoom through 4.5 billion years of Earth history, read the order of rock layers, turn a fish into a fossil and date rocks with radioactive half-lives.
~20 min
Weathering, Erosion and Landform Formation
Watch rain and rivers reshape a 3D landscape, crack rock with ice and roots, test what water, wind, ice and gravity can move, and grow deltas, meanders and dunes.
~20 min
Groundwater and Aquifer Systems
Slice open a 3D aquifer, pour water through sand, clay and fractured rock, pump a well into a cone of depression, apply Darcy’s law and track a pollution plume.
~20 min
Ecosystem Population Dynamics
Set predator and prey populations and watch their numbers rise and fall over time.
~15 min
Carbon Cycle
Move carbon between the atmosphere, oceans, living things and rocks.
~15 min
Climate Change
Change greenhouse gas levels in a simplified climate model and observe the temperature response.
~15 min
Biodiversity and Ecosystem Stability
Add and remove species and test how diversity affects an ecosystem’s resilience.
~15 min
Pollution and Environmental Impact
Introduce pollutants into a simulated lake and track their effects on life.
~15 min
3D Geometry Explorer
Rotate and resize 3D shapes and watch their surface area and volume update.
~12 min
Vector Addition
Drag vectors to change their size and direction and see the resultant form.
~12 min
Graphing Functions
Change parameters in an equation and watch the graph shift, stretch and flip.
~15 min
Probability and Random Experiments
Flip coins and roll dice thousands of times and watch distributions take shape.
~12 min
Scientific Data Visualization
Change variables in a dataset and learn how charts can reveal — or hide — patterns.
~12 min
Calculus Explorer: Limits, Derivatives and Integrals
Approach limits from both sides, drag tangent and secant lines, fill areas with Riemann sums and see how derivatives and integrals undo each other.
~25 min
Matrix Transformations and Linear Algebra
Multiply and invert matrices step by step, transform shapes in 2D and 3D, see determinants as area and find the vectors a matrix only stretches.
~25 min
Fractals and Recursive Patterns
Zoom into the Mandelbrot set, morph Julia sets, build the Sierpinski triangle and Koch snowflake, and grow a fern from four simple rules.
~20 min
Differential Equations and Dynamic Systems
Run exponential growth, cooling, a damped spring and logistic growth, explore phase planes, and see how step size makes Euler’s method succeed or fail.
~25 min
Optimization and Constraint Modeling
Drag constraints to build a linear program, find the best corner, test binding constraints and shadow prices, design a fence, box and can with calculus, and plan production.
~25 min
Browse by branch
Biology
How living things work, from molecules to populations.
- Osmosis and Cell TonicityLive
- Cell Structure and OrganellesLive
- Photosynthesis and the Light ReactionsLive
- DNA ReplicationLive
- Natural Selection and EvolutionLive
- Cellular Respiration and ATP ProductionLive
- Mitosis and the Cell CycleLive
- Meiosis and Genetic VariationLive
- Mendelian Genetics and InheritanceLive
- Ecosystem Energy Flow and Nutrient CyclingLive
Chemistry
Atoms, bonds and the reactions that rearrange them.
- Atomic StructureLive
- Chemical BondingLive
- Balancing Chemical EquationsLive
- Acid-Base ReactionsLive
- Reaction RatesLive
- States of Matter and Particle MotionLive
- Gas Laws and PressureLive
- Solutions, Solubility and ConcentrationLive
- Oxidation–Reduction and Electron TransferLive
- Electrochemistry: Galvanic Cells and ElectrolysisLive
Anatomy and Physiology
The structure and function of the human body.
- Human Heart and Blood CirculationLive
- Respiratory SystemLive
- Human Skeletal SystemLive
- Nervous System and Neuron FiringLive
- Digestive SystemLive
- Urinary System and Kidney FunctionLive
- Human Reproductive SystemLive
- Endocrine System and Hormonal RegulationLive
- Immune System and Defence Against DiseaseLive
- Muscular System and Muscle ContractionLive
Astronomy and Space Science
Planets, stars and the gravity that shapes the universe.
- Solar System ExplorerLive
- Phases of the MoonLive
- Planetary Orbits and GravityLive
- Stellar Life CycleLive
- Black Holes and Gravitational LensingLive
- Solar and Lunar EclipsesLive
- Seasons and Earth’s Axial TiltLive
- Tides and the Earth–Moon–Sun SystemLive
- Exoplanets and the Transit MethodLive
- Cosmic Expansion and RedshiftLive
Zoology and Animal Science
The diversity, behaviour and survival of animals.
- Animal ClassificationLive
- Animal Cell vs. Plant CellLive
- Animal AdaptationsLive
- Food Chains and Food WebsLive
- Animal LocomotionLive
- Animal Circulatory SystemsLive
- Animal Respiratory Systems and Gas ExchangeLive
- Animal Reproduction and Life CyclesLive
- Animal Nervous System and Sensory ResponsesLive
- Animal Behavior and Biological RhythmsLive
Botany and Plant Science
How plants are built, grow, reproduce and defend themselves.
- Plant Cell StructureLive
- Plant AnatomyLive
- TranspirationLive
- Seed GerminationLive
- Plant Growth and TropismsLive
- Plant Adaptations and Environmental SurvivalLive
- Plant Diversity and Life CyclesLive
- Plant Reproduction: Pollination and FertilisationLive
- Plant Hormones and Growth RegulationLive
- Plant Defense and Plant–Pathogen InteractionsLive
Physics and Mechanics
Forces, motion, fluids, waves, light and electricity.
- Newton’s Laws of MotionLive
- Projectile MotionLive
- Pendulum MotionLive
- Wave InterferenceLive
- Electricity and CircuitsLive
- Inclined Planes and FrictionLive
- Rotational Motion, Torque and Angular MomentumLive
- Momentum and CollisionsLive
- Fluid Mechanics, Pressure and BuoyancyLive
- Geometric Optics: Reflection, Refraction and LensesLive
Earth Science and Geology
The forces that build mountains, shake the ground and move water and air.
- Plate TectonicsLive
- Rock CycleLive
- Earth’s LayersLive
- Weather and Atmospheric ConditionsLive
- Water CycleLive
- Earthquakes and Seismic WavesLive
- Volcanoes and Volcanic EruptionsLive
- Geological Time and Fossil FormationLive
- Weathering, Erosion and Landform FormationLive
- Groundwater and Aquifer SystemsLive
Ecology and Environmental Science
How organisms interact with each other and the planet.
- Ecosystem Population DynamicsLive
- Carbon CycleLive
- Climate ChangeLive
- Biodiversity and Ecosystem StabilityLive
- Pollution and Environmental ImpactLive
Mathematics and Scientific Modeling
The language scientists use to describe, model and predict the world.
- 3D Geometry ExplorerLive
- Vector AdditionLive
- Graphing FunctionsLive
- Probability and Random ExperimentsLive
- Scientific Data VisualizationLive
- Calculus Explorer: Limits, Derivatives and IntegralsLive
- Matrix Transformations and Linear AlgebraLive
- Fractals and Recursive PatternsLive
- Differential Equations and Dynamic SystemsLive
- Optimization and Constraint ModelingLive