What is the junction between a motor neuron and the sarcolemma of...

The HMM component consists of the head and short arm of a meromyosin. The cross arm in the HMM component refers to the head and short arm projecting outwards at regular distance and angle from each other from the surface of a polymerised myosin filament.Muscle contraction is initiated by a signal sent by the central nervous system (CNS) via a motor neuron.The junction between a motor neuron and the sarcolemma of the muscle fibre is called the neuromuscular junction or motor-end plate.When a neural signal reaches the neuromuscular junction, it releases a neurotransmitter (Acetylcholine) which generates an action potential in the sarcolemma.