Which neurotransmitter connects a motor neuron and a muscle cell?
 

Solution:

Concept: Acetylcholine is the neurotransmitter that connects a motor neuron with a muscle cell. In the synaptic knob, the neurotransmitter is held in synaptic vesicles. 

It is released at the neuromuscular junction after the axon generates an action potential, which diffuses out across the synaptic cleft and attaches to nicotinic acetylcholine receptors (nAChRs) on the muscle fiber's cell membrane.