The Nerve ImpulseThe action potential, plotted and explained.BiologyOne action potential, about 1 millisecond.1Resting potential −70 mVMaintained by the Na⁺/K⁺ pump and leak channels.2Threshold −55 mVVoltage-gated sodium channels open.3Depolarisation to +40 mVSodium floods in.4RepolarisationSodium channels close, potassium channels open.5HyperpolarisationOvershoot below resting; the refractory period.WHY IT MATTERSAll-or-nothing: size never variesIntensity is coded by frequencyRefractory period ensures one-way travelMyelination speeds conduction enormouslyThe refractory period is what makes impulses travel in one directionand sets the maximum firing frequency.The Nerve Impulselearnposters.com
The Nerve Impulse — printable life science wall chart from LearnPosters. Free vector PDF, US Letter and A4.

The Nerve Impulse, step by step

One action potential, about 1 millisecond.

  1. Resting potential −70 mVMaintained by the Na⁺/K⁺ pump and leak channels.
  2. Threshold −55 mVVoltage-gated sodium channels open.
  3. Depolarisation to +40 mVSodium floods in.
  4. RepolarisationSodium channels close, potassium channels open.
  5. HyperpolarisationOvershoot below resting; the refractory period.

Why it matters

  • All-or-nothing: size never varies
  • Intensity is coded by frequency
  • Refractory period ensures one-way travel
  • Myelination speeds conduction enormously

The refractory period is what makes impulses travel in one direction and sets the maximum firing frequency.

Questions about the The Nerve Impulse poster

What’s on the The Nerve Impulse poster?
5 numbered steps, with a full worked run-through. One action potential, about 1 millisecond. Resting potential −70 mV — Maintained by the Na⁺/K⁺ pump and leak channels.; Threshold −55 mV — Voltage-gated sodium channels open.; Depolarisation to +40 mV — Sodium floods in.; Repolarisation — Sodium channels close, potassium channels open.; Hyperpolarisation — Overshoot below resting; the refractory period.. The refractory period is what makes impulses travel in one direction and sets the maximum firing frequency.
Who is the The Nerve Impulse poster for?
The Nerve Impulse belongs to the Biology section rather than to a school year, because life science is not something one grade owns. Anyone learning physiology can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the The Nerve Impulse poster?
Sodium in depolarises. Potassium out repolarises. The pump restores the gradients afterwards. A wall chart earns its place by being glanceable from where the work is happening, so The Nerve Impulse belongs on the wall where that life science work actually happens, within glancing distance, rather than filed away.
What other posters go with The Nerve Impulse?
Blood Glucose Control, The Cardiac Cycle and The Circulatory System sit alongside The Nerve Impulse in the Biology section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Blood Glucose ControlThe Cardiac CycleThe Circulatory System
Is the The Nerve Impulse poster free to download and print?
Yes. The Nerve Impulse downloads as a free PDF with no account, no email and no watermark, like everything else in the Biology section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the The Nerve Impulse poster print at?
The Nerve Impulse is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of The Nerve Impulse loses nothing.Printing guide

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