Biology / Unit 13 Bio 3117 short lesson, about 20 seconds
Neuromuscular Junction and Excitation-Contraction Coupling
Captions available
The idea
At the neuromuscular junction, acetylcholine, per Bio 2827, triggers a muscle action potential that spreads inward and releases calcium, coupling nerve excitation to filament sliding.
In practice
The action potential travels down T-tubules to calcium stores deep inside the fiber.
Where people slip
The action potential does not slide filaments directly — it triggers the calcium release that does.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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