What delivers a signal from the motor neuron to all the sarcomeres of a muscle cell?

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Quizplus · Accepted Answer

The transverse tubules, also known as T-tubules, are extensions of the sarcolemma (cell membrane) that penetrate deep into the muscle cell, running perpendicular to the myofibrils. They allow an action potential (signal) from the motor neuron to spread quickly and uniformly throughout the muscle cell, triggering the release of calcium ions from the sarcoplasmic reticulum and ultimately leading to muscle contraction. Therefore, the transverse tubules deliver the signal from the motor neuron to all the sarcomeres of a muscle cell.

What Delivers a Signal from the Motor Neuron to All