What impulse travels along the sarcolemma to the transverse tubules?

The impulse that travels along the sarcolemma to the transverse tubules is an action potential. When a muscle fiber is stimulated by a motor neuron, the action potential propagates along the sarcolemma, causing depolarization. This electrical signal then travels into the transverse tubules, facilitating the release of calcium ions from the sarcoplasmic reticulum, which is crucial for muscle contraction.