SimulateEd

Science you can poke at.

Eight simulations built on the real models. This neuron is running now. Fire a pulse and watch it spike.

Membrane voltage over the last 120 ms. Dashed line is threshold, -55 mV.

-65.0Voltage (mV)

-Last peak (mV)

-Afterdip (mV)

Biology

Neuron action potential
Stimulate a labeled neuron and follow a real action potential from the cell body, down the myelinated axon, to the synapse. Runs a full Hodgkin-Huxley model.
Open
Cardiac action potential
Explore a heart cell's calcium-supported plateau, compare it with a neuron, and measure recovery with paired-pulse experiments.
Open
DNA replication
Watch helicase open the fork while DNA polymerase builds the leading strand in one piece and the lagging strand in Okazaki fragments.
Open

Chemistry

Molecular orbitals
Build s, p and d orbitals in 3D, then combine two atoms into σ and π bonding and antibonding orbitals, with bond order worked out for you.
Open

Physics

Mathematics

Fourier series
Draw any wave or pick a preset, then watch rotating circles rebuild it one harmonic at a time, with its frequency spectrum alongside.
Open

Astronomy

Solar system
A model of the solar system whose orbits follow Kepler's laws. Click any planet to compare its distance, period and eccentricity.
Open

Each page

Learn the goalIt opens with what you'll learn, so you know what to look for.
Experiment"Try this" steps walk you through the key experiments. Then change anything.
UnderstandIt ends with the science and equations behind what you just saw.