National Certified Addiction Counselor, Level 2 (NCAC II) Practice Exam Exam

Which neurotransmitter is primarily responsible for muscle movement?

1. Dopamine

2. Norepinephrine

3. Serotonin

4. Acetylcholine

The correct answer is: Acetylcholine

Acetylcholine is the neurotransmitter that plays a crucial role in muscle movement. It is released at neuromuscular junctions, where nerve cells communicate with muscle fibers to trigger contraction. When a nerve impulse reaches the end of a motor neuron, acetylcholine is released into the synaptic cleft. This binding initiates a series of events that ultimately results in muscle contraction, enabling movement. While dopamine, norepinephrine, and serotonin each play important roles in various functions within the central nervous system, they are not primarily responsible for muscle movement. Dopamine is significantly involved in reward and motivation processes and plays a role in the coordination of movement, especially in relation to motor control and the regulation of emotions. Norepinephrine is largely involved in the body's response to stress and influences attention and responding actions in the brain. Serotonin primarily impacts mood, emotion, and sleep, among other functions, but it does not directly facilitate muscle movement in the way that acetylcholine does.