Question

musle contraction requires​

Answer 1

The muscle contraction cycle is triggered by calcium ions binding to the protein complex troponin, exposing the active-binding sites on the actin. ... ATP then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.

Answer 2

A single motor neuron is able to innervate multiple muscle fibers, thereby causing the fibers to contract at the same time. Once innervated, the protein filaments within each skeletal muscle fiber slide past each other to produce a contraction, which is explained by the sliding filament theory