Nerve Signals That Trigger Muscle Contraction

Nerve signals trigger muscle contraction in both skeletal and smooth muscle, but the two muscle types use different control systems. In skeletal muscle, the signal begins at the motor end plate, which is the synapse between a motor neuron and a muscle fiber. In smooth muscle, contraction is controlled by the autonomic nervou...

A voluntary skeletal muscle contraction begins in the brain as a conscious effort from the frontal lobe to the primary motor cortex, before activating, an alpha motor neuron located in the anterior horn of the spinal cord.

The signal continues down a nerve to the specific muscle fiber such as those found in the biceps, where the action p...