Action Potential — Neuron Firing

Description

A neuron diagram with a voltage-time graph showing all phases of an action potential. Ion animations (Na+ rushing in, K+ rushing out) are synchronized with the graph. The signal propagates down the axon at the end.

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Phases

#	Phase Name	Duration	Description
1	Setup	4s	Neuron diagram (cell body + long axon) appears, voltage graph axes
2	Resting Potential	4s	Membrane at -70mV, Na+/K+ distribution shown, graph holds flat
3	Threshold	3s	Stimulus arrow, membrane voltage rises to -55mV threshold line
4	Depolarization	5s	Na+ channels open, Na+ rushes in, graph spikes to +40mV
5	Repolarization	5s	K+ channels open, K+ rushes out, graph falls back toward rest
6	Hyperpolarization	4s	Voltage dips below -70mV briefly (undershoot)
7	Return to Rest	3s	Na+/K+ pump restores balance, voltage returns to -70mV
8	Propagation	8s	Signal (wave of color) propagates down the axon
9	Summary	4s	Key values labeled on graph, "All-or-Nothing" principle shown

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Layout

+------------------------------------------------------+
|  Action Potential — Neuron Firing                    |
|                                                      |
|  [Neuron diagram — top half]                         |
|  (o)--- axon ----------------------------------------|
|  Na+ ↓↓↓ K+ ↑↑↑ (ion animation on membrane)         |
|                                                      |
|  [Voltage graph — bottom half]                       |
|       +40mV ─────  ↑ depolarization                  |
|         0mV ─────                                    |
|       -55mV - - -  threshold                         |
|       -70mV ─────  resting potential                 |
|              time →                                  |
+------------------------------------------------------+

Area Descriptions

• Top portion: stylized neuron with cell body, dendrites, long axon, myelin sheaths
• Middle: ion animation zone showing Na+ (red) and K+ (blue) crossing membrane
• Bottom: voltage vs time graph with labeled phases

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Assets & Dependencies

• Fonts: LaTeX / sans-serif
• Manim version: ManimCE 0.19.1

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Notes

• Na+: red/orange circles with "Na+" label
• K+: blue/teal circles with "K+" label
• Graph line traced in real time using VMobject path building
• Resting -70mV, threshold -55mV, peak +40mV, undershoot -80mV
• Propagation shown as a traveling colored glow along the axon