Question

The neurotransmitter between a motor neuron and a muscle cell is

• A. Serotonin
• B. Endorphin
• C. Dopamine
• D. Acetylcholine

Answer 1

Answer: (D)

Acetylcholine

The neurotransmitter between a motor neuron and a muscle cell is acetylcholine. The neurotransmitter is stored in the synaptic vesicles in the synaptic knob. It is released at the neuromuscular junction after stimulation from the action potential generated in the axon which diffuses across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChRs) on the cell membrane of the muscle fiber. The binding of ACh to the receptor can depolarize the muscle fiber. The depolarized muscle fibre releases calcium ions and causes muscle contraction.

So, the correct answer is 'Acetylcholine'.